Ok.. so...
I downloaded the ferrari enzo 2003 version it has the .txd, .dff and z3d files
Now, I got imagetool2 the one you can use with SA and I found a car I wanted to replace with the ferrari, first, I noticed if I right clicked there was an option to replace so I clicked replace and clicked on the .txd file of the ferrari, I played the game and when I spawned the car nothing appeared, I found this strange so I tried again with another car but this time, I backuped and deleted the file then inserted the ferrari file named the same as the original car.
I know i've missed out something or w/e
Help please?