Texturing with Truespace 1: AAAARRRRGGGGG!!!
I think the easyiest way is to get on your knees and pray to your God (and all other gods) for a miracle.
TS1 can only apply one UV space to the entire model, and unfortunately the FS models are not built to work this way. FS fighter skins contain multiple textures that are supposed to be placed at certain faces, not simply slapped around the model on a big sphere.
You COULD try to use a spherical UV space and carefully move every single texture into position, but I Don't give any guarantee that this will bring any results. I rather think the spherical UV will warp the skin so the textures will not fit into their appropiate places.