Battle Isle Total Conversion - Problem with new 3D-Models (not replaceing existing Models)

[Spydox]

Hello! I am currently working on a total conversion for PC2 based on Battle Isle 2/3. I have already converted all the Battle Isle 2/3 assets into high-quality 3D models. They work in PC2, but I have to "overwrite" an existing model to use them—which isn't really practical given there are 63 models. Many other attempts to import completely new models have failed so far (usually resulting in crashes in the purchase menu). Mapping new unit types via `Units.csv` works fine.

So, here is my question—one I haven't found an answer to anywhere else:
How can I integrate completely new models into PC2 without overwriting existing ones? There must be some central registration files or similar somewhere...

I hope you can help me; otherwise, I’ll have to switch to *Order of Battle*, which I’d ​​rather not do since PC2 is more modern.