FIB Buffalo Help

So, I imported the FIB Buffalo from GTA IV into Zmodeler 2.0.8, and exported it as old .z3d. Now, I opened both it, and Mafia 1's Trantunberg into one file. I got all the parts lined up, and named. What I need help on is how to assign what they are, textures, and basicly anythi g else I need to know.