If you want to install textures you can drag the textures to your desktop.Then go into sparkiv and go to vehicle.img file.Then you go to the car location to where you want the textures.For example police.You want to highlight the wtd file and at the top of your screen hit the edit button.Then you want to find the police signs.You highlight the police signs and where it says import texture import the texture you want.Make sure the texture fits the model some models don't fit all textures.Hope this helps you.
FCSO_SHERIFF.