Any changes to the GM require the following:
1. Convert model to OBJ using GM Viewer
2. Import OBJ into Maya
3. Fix whatever went wrong in this export process
4. Make whatever adjustments are desired to the model file
5. Export again, with the correct settings so the new model will work just as well as the old one
Only exceptions are:
- HEX Editing the model to apply a different texture; this does not affect the UV map in any way
- Adding extra details using TOOL; as @Armada mentioned, these extra details can be affected by the "reverse lighting bug"
In other words, not a whole lot that can be done to the model itself without a LOT of extra work.
It would be far easier if we had the original Maya source files. But for most ships, we don't.
Well poo. Why does everything have to be so complex?