diff --git a/convert-hf-to-gguf.py b/convert-hf-to-gguf.py
index 7c8d7a8ac75ea..24da4ebdd941e 100644
--- a/convert-hf-to-gguf.py
+++ b/convert-hf-to-gguf.py
@@ -2570,7 +2570,7 @@ def main() -> None:
     if args.split_max_tensors and args.split_max_size:
         raise ValueError("Can't specify both --split-max-tensors and --split-max-size")
 
-    split_arguments = gguf.SplitArguments(args) if args.split else gguf.SplitArguments()
+    split_arguments = gguf.SplitArguments(args=args) if args.split else gguf.SplitArguments()
 
     ftype_map = {
         "f32": gguf.LlamaFileType.ALL_F32,
diff --git a/convert.py b/convert.py
index 26c0641250b0c..da1247957780c 100644
--- a/convert.py
+++ b/convert.py
@@ -24,17 +24,14 @@
 from concurrent.futures import ProcessPoolExecutor, ThreadPoolExecutor
 from dataclasses import dataclass
 from pathlib import Path
-from typing import TYPE_CHECKING, Any, Callable, ClassVar, IO, Iterable, Literal, Protocol, TypeVar, runtime_checkable
-# TEMPORARY IMPORT - TODO REMOVE
-import importlib
-gguf = importlib.import_module("gguf-py.gguf")
+from typing import TYPE_CHECKING, Any, Callable, ClassVar, IO, Iterable, Literal, Protocol, TypeVar, runtime_checkable, Optional
 
 import numpy as np
 from sentencepiece import SentencePieceProcessor
 
 if 'NO_LOCAL_GGUF' not in os.environ:
     sys.path.insert(1, str(Path(__file__).parent / 'gguf-py'))
-# import gguf
+import gguf
 
 if TYPE_CHECKING:
     from typing_extensions import Self, TypeAlias
@@ -1103,8 +1100,8 @@ def check_vocab_size(params: Params, vocab: BaseVocab, pad_vocab: bool = False)
 
 
 class OutputFile:
-    def __init__(self, fname_out: Path, split_arguments: gguf.SplitArguments, endianess:gguf.GGUFEndian = gguf.GGUFEndian.LITTLE):
-        self.gguf = gguf.GGUFManager(fname_out, gguf.MODEL_ARCH_NAMES[ARCH], split_arguments, endianess=endianess)
+    def __init__(self, fname_out: Path, endianess:gguf.GGUFEndian = gguf.GGUFEndian.LITTLE):
+        self.gguf = gguf.GGUFWriter(fname_out, gguf.MODEL_ARCH_NAMES[ARCH], endianess=endianess)
 
     def add_meta_model(self, params: Params, metadata: Metadata) -> None:
         # Metadata About The Model And Its Provenence
@@ -1204,15 +1201,21 @@ def add_meta_vocab(self, vocab: Vocab) -> None:
     def add_meta_special_vocab(self, svocab: gguf.SpecialVocab) -> None:
         svocab.add_to_gguf(self.gguf)
 
+    def add_tensor_info(self, name: str, tensor: LazyTensor) -> None:
+        n_elements = int(np.prod(tensor.shape))
+        raw_dtype = getattr(tensor.data_type, 'ggml_type', None)
+        data_type = getattr(tensor.data_type, 'quantized_type', None) or tensor.data_type.dtype
+        data_nbytes = tensor.data_type.elements_to_bytes(n_elements)
+        self.gguf.add_tensor_info(name, tensor.shape, data_type, data_nbytes, raw_dtype=raw_dtype)
+
     def write_meta(self) -> None:
-        self.gguf.write_to_file(meta_only=True)
+        self.gguf.write_header_to_file()
+        self.gguf.write_kv_data_to_file()
 
-    def write_tensors(self, ftype: GGMLFileType, concurrency: int) -> None:
-        self.gguf.write_to_file(ftype=ftype, concurrency=concurrency, write_tensor_data=OutputFile.write_tensor_data)
+    def write_tensor_info(self) -> None:
+        self.gguf.write_ti_data_to_file()
 
-    # really awkward with how this is managed with gguf_manager.py: maybe refactor at some point?
-    @staticmethod
-    def write_tensor_data(ftype: GGMLFileType, model: LazyModel, concurrency: int, writer: gguf.GGUFWriter) -> None:
+    def write_tensor_data(self, ftype: GGMLFileType, model: LazyModel, concurrency: int) -> None:
         ndarrays_inner = bounded_parallel_map(OutputFile.do_item, model.items(), concurrency=concurrency)
         if ftype == GGMLFileType.MostlyQ8_0:
             ndarrays = bounded_parallel_map(
@@ -1230,7 +1233,7 @@ def write_tensor_data(ftype: GGMLFileType, model: LazyModel, concurrency: int, w
             logger.info(
                 f"[{i + 1:{padi}d}/{len(model)}] Writing tensor {name:38s} | size {size:16} | type {lazy_tensor.data_type.name:4} | T+{int(elapsed):4}"
             )
-            writer.write_tensor_data(ndarray)
+            self.gguf.write_tensor_data(ndarray)
 
     def close(self) -> None:
         self.gguf.close()
@@ -1242,7 +1245,7 @@ def write_vocab_only(
     ) -> None:
         check_vocab_size(params, vocab, pad_vocab=pad_vocab)
 
-        of = OutputFile(fname_out, gguf.SplitArguments(), endianess=endianess)
+        of = OutputFile(fname_out, endianess=endianess)
 
         # meta data
         of.add_meta_model(params, metadata)
@@ -1270,11 +1273,13 @@ def maybe_do_quantize(item: tuple[DataType, NDArray]) -> NDArray:
     @staticmethod
     def write_all(
         fname_out: Path, ftype: GGMLFileType, params: Params, model: LazyModel, vocab: BaseVocab, svocab: gguf.SpecialVocab,
-        split_arguments: gguf.SplitArguments, concurrency: int = DEFAULT_CONCURRENCY, endianess: gguf.GGUFEndian = gguf.GGUFEndian.LITTLE,
-        pad_vocab: bool = False, metadata: Metadata = None,
+        concurrency: int = DEFAULT_CONCURRENCY, endianess: gguf.GGUFEndian = gguf.GGUFEndian.LITTLE,
+        pad_vocab: bool = False,
+        metadata: Metadata = None,
     ) -> None:
         check_vocab_size(params, vocab, pad_vocab=pad_vocab)
-        of = OutputFile(fname_out, split_arguments, endianess=endianess)
+
+        of = OutputFile(fname_out, endianess=endianess)
 
         # meta data
         of.add_meta_model(params, metadata)
@@ -1287,9 +1292,13 @@ def write_all(
 
         # tensor info
         for name, lazy_tensor in model.items():
-            of.gguf.add_tensor_info(name, lazy_tensor)
+            of.add_tensor_info(name, lazy_tensor)
+
+        of.write_meta()
+        of.write_tensor_info()
 
-        of.write_tensors(ftype, concurrency)
+        # tensor data
+        of.write_tensor_data(ftype, model, concurrency)
 
         of.close()
 
@@ -1364,7 +1373,7 @@ def convert_model_names(model: LazyModel, params: Params, skip_unknown: bool) ->
                         experts.append(model[f"model.layers.{i_l}.block_sparse_moe.experts.{e}.w{w}.weight"])
                         del tmp[f"model.layers.{i_l}.block_sparse_moe.experts.{e}.w{w}.weight"]
                     else:
-                        raise ValueError(f"Expert tensor not found: layers.{i_l}.feed_forward.experts.{e}.w{w}.model_classweight")
+                        raise ValueError(f"Expert tensor not found: layers.{i_l}.feed_forward.experts.{e}.w{w}.weight")
                 tmp[f"layers.{i_l}.feed_forward.experts.w{w}.weight"] = pack_experts_lazy(experts)
 
     # HF models permut or pack some of the tensors, so we need to undo that
@@ -1584,11 +1593,6 @@ def main(args_in: list[str] | None = None) -> None:
     parser.add_argument("--big-endian",   action="store_true",    help="model is executed on big endian machine")
     parser.add_argument("--pad-vocab",    action="store_true",    help="add pad tokens when model vocab expects more than tokenizer metadata provides")
     parser.add_argument("--skip-unknown", action="store_true",    help="skip unknown tensor names instead of failing")
-    parser.add_argument("--split", action="store_true", help="split the converted model into multiple files")
-    parser.add_argument("--split-max-tensors", type=int, help="max tensors in each split")
-    parser.add_argument("--split-max-size", type=str, help="max size per split N(M|G)")
-    parser.add_argument("--dry-run", action="store_true", help="only print out a split plan and exit, without writing any new files")
-    parser.add_argument("--large-first-shard", action="store_true", help="include tensors in the first shard when splitting (default: metadata only)")
     parser.add_argument("--verbose",      action="store_true",    help="increase output verbosity")
     parser.add_argument("--metadata",     type=Path,              help="Specify the path for a metadata file")
     parser.add_argument("--get-outfile",  action="store_true",    help="get calculated default outfile name")
@@ -1622,14 +1626,6 @@ def main(args_in: list[str] | None = None) -> None:
         do_dump_model(model_plus)
         return
 
-    if args.split and not (args.split_max_tensors or args.split_max_size):
-        raise ValueError("Need to specify one of --split-max-tensors or --split-max-size when splitting")
-
-    if args.split_max_tensors and args.split_max_size:
-        raise ValueError("Can't specify both --split-max-tensors and --split-max-size")
-
-    split_arguments = gguf.SplitArguments(args) if args.split else gguf.SplitArguments()
-
     if not args.vocab_only:
         model_plus = load_some_model(args.model)
     else:
@@ -1707,13 +1703,11 @@ def main(args_in: list[str] | None = None) -> None:
     outfile = args.outfile or default_outfile(model_plus.paths, ftype, params, model_params_count, metadata)
 
     params.ftype = ftype
-
     logger.info(f"Writing {outfile}, format {ftype}")
 
-    OutputFile.write_all(outfile, ftype, params, model, vocab, special_vocab, split_arguments,
+    OutputFile.write_all(outfile, ftype, params, model, vocab, special_vocab,
                          concurrency=args.concurrency, endianess=endianess, pad_vocab=args.pad_vocab, metadata=metadata)
-    if not args.dry_run:
-        logger.info(f"Wrote {outfile}")
+    logger.info(f"Wrote {outfile}")
 
 
 if __name__ == '__main__':
diff --git a/gguf-py/gguf/gguf_manager.py b/gguf-py/gguf/gguf_manager.py
index f36b0173eafae..4a51b717e23e6 100644
--- a/gguf-py/gguf/gguf_manager.py
+++ b/gguf-py/gguf/gguf_manager.py
@@ -10,6 +10,7 @@
 from string import ascii_letters, digits
 from argparse import Namespace
 from math import ceil
+from collections import deque
 
 import numpy as np
 
@@ -34,7 +35,7 @@
 LLM_KV_SPLIT_COUNT = "split.count"
 LLM_KV_SPLIT_TENSORS_COUNT = "split.tensors.count"
 
-SplitTensorsPerFile: TypeAlias = list[tuple[os.PathLike[str], list[tuple[str, Any]], GGUFWriter]] # [(outfile name, [(tensor name, tensor data)] for each tensor in file, filewriter)]
+SplitTensorsPerFile: TypeAlias = deque[tuple[os.PathLike[str], deque[tuple[str, Any]], GGUFWriter]] # [(outfile name, [(tensor name, tensor data)] for each tensor in file, filewriter)]
 KVTempData: TypeAlias = dict[str, tuple[Any, GGUFValueType]] # {key: (value, type)}
 TensorTempData: TypeAlias = tuple[str, np.ndarray[Any, Any]] # (tensor name, tensor data), aka LazyModel
 
@@ -53,23 +54,23 @@ class SplitArguments:
     split_max_size: int
     split_style: SplitStyle
 
-    def __init__(self) -> None:
-        self.split = False
-        self.dry_run = False
-        self.small_first_shard = False
-        self.split_max_tensors = 0
-        self.split_max_size = 0
-        self.split_style = SplitStyle.NONE
-
-    def __init__(self, args: Namespace) -> None:
-        self.split = args.split
-        self.split_max_tensors = args.split_max_tensors
-        self.split_max_size = SplitStrategy.split_str_to_n_bytes(args.split_max_size) if args.split_max_size else None
-        self.dry_run = args.dry_run
-        self.small_first_shard = not args.large_first_shard
-        self.split_style = SplitStyle.NONE if not self.split \
-            else SplitStyle.TENSORS if self.split_max_tensors \
-            else SplitStyle.SIZE
+    def __init__(self, args: Namespace = None) -> None:
+        if args is None:
+            self.split = False
+            self.dry_run = False
+            self.small_first_shard = False
+            self.split_max_tensors = 0
+            self.split_max_size = 0
+            self.split_style = SplitStyle.NONE
+        else:
+            self.split = args.split
+            self.split_max_tensors = args.split_max_tensors
+            self.split_max_size = SplitStrategy.split_str_to_n_bytes(args.split_max_size) if args.split_max_size else None
+            self.dry_run = args.dry_run
+            self.small_first_shard = not args.large_first_shard
+            self.split_style = SplitStyle.NONE if not self.split \
+                else SplitStyle.TENSORS if self.split_max_tensors \
+                else SplitStyle.SIZE
 
 
 class SplitStrategy:
@@ -78,7 +79,7 @@ class SplitStrategy:
     def __init__(self, fname_out: os.PathLike[str], model: list[TensorTempData], arch: str,
                  split_arguments: SplitArguments, use_temp_file: bool = True, endianess: GGUFEndian = GGUFEndian.LITTLE,
     ):
-        self.data = []
+        self.data = deque()
 
         if split_arguments.split_style == SplitStyle.NONE:
             self.append((fname_out, model, GGUFWriter(fname_out, arch, use_temp_file=use_temp_file, endianess=endianess)))
@@ -96,7 +97,7 @@ def __init__(self, fname_out: os.PathLike[str], model: list[TensorTempData], arc
                 self.append((shard, model[start:stop], GGUFWriter(shard, arch, use_temp_file=use_temp_file, endianess=endianess)))
 
         elif split_arguments.split_style == SplitStyle.SIZE:
-            shards = []
+            shards = deque()
 
             # we have to determine the shards first to determine how many shards there will be in total - two passes
             for i, shard in enumerate(model):
@@ -118,13 +119,7 @@ def __init__(self, fname_out: os.PathLike[str], model: list[TensorTempData], arc
 
             for i, shard in enumerate(shards):
                 outname = fname_out.with_name(SHARD_NAME_FORMAT.format(fname_out.stem, i + shard_offset, total_shards))
-                self.append((outname, shard, GGUFWriter(outname, arch, use_temp_file=use_temp_file, endianess=endianess)))
-
-    def __getitem__(self, index):
-        return self.data[index]
-    
-    def __setitem__(self, index, value):
-        self.data[index] = value
+                self.append((outname, deque(shard), GGUFWriter(outname, arch, use_temp_file=use_temp_file, endianess=endianess)))
 
     def __len__(self):
         return len(self.data)
@@ -176,7 +171,7 @@ def format_n_bytes_to_str(num: int) -> str:
 # ideally this has most of the same signatures as GGUFWriter so it's nearly a drop-in replacement
 class GGUFManager:
     kv_data: KVTempData
-    tensors: list[TensorTempData]
+    tensors: deque[TensorTempData]
     split_arguments: SplitArguments
     split_strategy: SplitStrategy
 
@@ -188,7 +183,7 @@ def __init__(self, path: os.PathLike[str] | str, arch: str, split_arguments: Spl
         self.endianess = endianess
         self.offset_tensor = 0
         self.kv_data = {}
-        self.tensors = []
+        self.tensors = deque()
         self.split_strategy = None
         self.total_shards = None
         self.total_tensors = None
@@ -200,9 +195,7 @@ def __init__(self, path: os.PathLike[str] | str, arch: str, split_arguments: Spl
     # have to consolidate because we need to know kv data count and tensor count before we can write the header
     # and we need to write tensor info before we can write metadata
     # these all kinda show up around the same places anyway so it's not a huge deal?
-    def write_to_file(self, meta_only: bool = False, ftype: int = 0, concurrency: int = 8,
-                      write_tensor_data: function = None
-    ) -> None:
+    def write_to_file(self, meta_only: bool = False) -> None:
 
         # here is the first place you can assume you have all tensors written and you can establish the size of the file - so logic goes here
         self.total_tensors = len(self.tensors)
@@ -218,22 +211,23 @@ def write_to_file(self, meta_only: bool = False, ftype: int = 0, concurrency: in
 
         self.split_strategy = SplitStrategy(self.path, self.tensors, self.arch, self.split_arguments,
                                             use_temp_file=self.use_temp_file, endianess=self.endianess)
+        del self.tensors
         self.total_shards = len(self.split_strategy)
 
         # only the first shard needs all the KV data
         for key, (value, etype) in self.kv_data.items():
-            self.split_strategy[0][2].add_key(key)
-            self.split_strategy[0][2].add_val(value, etype)
+            self.split_strategy.data[0][2].add_key(key)
+            self.split_strategy.data[0][2].add_val(value, etype)
 
         if self.split_arguments.split_style != SplitStyle.NONE:
-            for i, (_, _, writer) in enumerate(self.split_strategy):
+            for i, (_, _, writer) in enumerate(self.split_strategy.data):
                 writer.add_uint16(LLM_KV_SPLIT_NO, i)
                 writer.add_uint16(LLM_KV_SPLIT_COUNT, self.total_shards)
                 writer.add_int32(LLM_KV_SPLIT_TENSORS_COUNT, self.total_tensors)
 
         # metadata/vocab only can write and return here
         if meta_only:
-            for i, (_, _, writer) in enumerate(self.split_strategy):
+            for i, (_, _, writer) in enumerate(self.split_strategy.data):
                 writer.write_header_to_file()
                 writer.write_kv_data_to_file()
             return
@@ -241,57 +235,44 @@ def write_to_file(self, meta_only: bool = False, ftype: int = 0, concurrency: in
         # tensor writing code starts here
 
         print("\nWriting the following files:")
-        for (shard_path, shard_tensors, _) in self.split_strategy:
+        for (shard_path, shard_tensors, _) in self.split_strategy.data:
             size = SplitStrategy.format_n_bytes_to_str(sum(SplitStrategy.get_tensor_size(t[1]) for t in shard_tensors)) if shard_tensors else "negligible - metadata only"
             print(f"  {shard_path}: n_tensors = {len(shard_tensors) if shard_tensors else 0}, total_size = {size}")
 
         if self.split_arguments.dry_run:
             print("\nDry run, not writing files")
             # instantiating GGUFWriters creates files
-            for name, _, _ in self.split_strategy:
+            for name, _, _ in self.split_strategy.data:
                 os.remove(name)
             return
 
         # run add_tensor_info, write data, then write_tensor_data - taken from convert.py
         running_total = self.total_tensors
-        start = time.time()
-        for i, (_, tensors, writer) in enumerate(self.split_strategy):
-
+        ct = 0
+        while True:
+            try:
+                (_, tensors, writer) = self.split_strategy.data.popleft()
+            except IndexError:
+                break
+
+            shard_num_tensors = len(tensors) if tensors else 0
+            
             if tensors:
-                print(f"\nWriting to shard {i + 1}/{self.total_shards} with {len(tensors)}/{running_total} remaining tensors (of {self.total_tensors} total)")
-                for j, (name, tensor) in enumerate(tensors):
-                    n_elements = int(np.prod(tensor.shape))
-                    # logic from convert.py
-                    if getattr(tensor, 'data_type', None):
-                        raw_dtype = getattr(tensor.data_type, 'ggml_type', None)
-                        data_type = getattr(tensor.data_type, 'quantized_type', None) or tensor.data_type.dtype
-                        data_nbytes = tensor.data_type.elements_to_bytes(n_elements)
-                        writer.add_tensor_info(name, tensor.shape, data_type, data_nbytes, raw_dtype=raw_dtype)
-                    # logic from convert-hf-to-gguf.py
-                    else:
-                        # stolen from write_tensor_data because that doesn't get called with this logic
-                        elapsed = time.time() - start
-                        size = ' x '.join(f"{dim:6d}" for dim in tensor.shape)
-                        padi = len(str(self.total_tensors))
-                        dtype = str(tensor.dtype)
-                        print(
-                            f"[{j + 1:{padi}d}/{len(tensors)}] Writing tensor {name:38s} | size {size:16} | type {dtype:8} | T+{int(elapsed):4}"
-                        )
-                        writer.add_tensor(name, tensor)
-                print(f"Writing to shard {i + 1}/{self.total_shards} with {len(tensors)}/{running_total} remaining tensors (of {self.total_tensors} total)")
+                while True:
+                    try:
+                        (name, tensor) = tensors.popleft()
+                    except IndexError:
+                        break
+                    writer.add_tensor(name, tensor)
 
+                print(f"Writing to shard {ct + 1}/{self.total_shards} with {shard_num_tensors}/{running_total} remaining tensors (of {self.total_tensors} total)")
+                running_total -= shard_num_tensors
 
             writer.write_header_to_file()
             writer.write_kv_data_to_file()
-            writer.write_tensors_to_file()
-
-            if tensors:
-                # TODO this shows up AFTER writing which we don't really want - move it
-                running_total -= len(tensors)
-
-                if write_tensor_data:
-                    # convert.py's write_tensor_data is dependent on so many objects in convert.py itself that it's easier to pass the function as a parameter and call it here
-                    write_tensor_data(ftype, dict(tensors), concurrency, writer)
+            writer.write_tensors_to_file(progress=True)
+            ct = ct + 1
+            del tensors
 
     def add_uint8(self, key: str, val: int) -> None:
         self.kv_data[key] = (val, GGUFValueType.UINT8)
@@ -336,11 +317,6 @@ def add_array(self, key: str, val: Sequence[Any]) -> None:
             raise ValueError(f'Expected a sequence for {key}, got {type(val)}')
         self.kv_data[key] = (val, GGUFValueType.ARRAY)
 
-    # this method is exclusive to convert.py - we don't have LazyTensor so Any type is used
-    def add_tensor_info(self, name: str, tensor: Any) -> None:
-        self.tensors.append((name, tensor))
-
-    # these methods are everywhere but convert.py (and convert-lora-to-ggml.py since that doesn't use the class)
     def add_tensor(
         self, name: str, tensor: np.ndarray[Any, Any], raw_shape: Sequence[int] | None = None,
         raw_dtype: GGMLQuantizationType | None = None,
@@ -354,7 +330,7 @@ def add_tensor(
         #    fp.seek(0)
         #    self.temp_file = fp
 
-        self.add_tensor_info(name, tensor)
+        self.tensors.append((name, tensor))
 
         #if self.temp_file is None:
         #    self.tensors.append(tensor)
@@ -363,12 +339,8 @@ def add_tensor(
         #tensor.tofile(self.temp_file)
         #self.write_padding(self.temp_file, tensor.nbytes)
 
-    def write_tensors_to_file(self) -> None:
-        # TODO WRITE
-        pass
-
     def close(self) -> None:
-        for _, _, writer in self.split_strategy:
+        for _, _, writer in self.split_strategy.data:
             writer.close()
 
     def add_architecture(self) -> None:
diff --git a/gguf-py/gguf/gguf_writer.py b/gguf-py/gguf/gguf_writer.py
index 8b41b54eaa5a6..964bf849c079a 100644
--- a/gguf-py/gguf/gguf_writer.py
+++ b/gguf-py/gguf/gguf_writer.py
@@ -301,6 +301,7 @@ def write_tensors_to_file(self, *, progress: bool = False) -> None:
                     tensor.tofile(self.fout)
                     bar.update(tensor.nbytes)
                     self.write_padding(self.fout, tensor.nbytes)
+                    del tensor
                 return
             while True:
                 try: