All the 3D information in the game is stored in .O files which can be edited (in theory) in OEdit. Again, in theory, you might be able to find a way of getting the information to 3DS Max through some third-party software like Milkshape or some such. Even if you do though, you will likely mess up the UVW mapping which will render all of our textures useless. I have actually tried doing all of this using numerous different bits of software including 3DS Max, Maya, Softimage XSi, Milkshape, etc., etc. but with no joy. I don't want to sound like a defeatist, but you may want to give up now.