The SFC2 Excelsior (FDN) is about 15% smaller than the SFC3 version. The model.siz file should take care of that. Also, the HPs are different (not just the locations but the numbers) and no LODs. It's low poly enough that any current system should have no problems running it. The SFC3 version could be converted very easily though. As it is, it will run. The weapons just wouldn't fire from the correct locations.