I have a question. I changed the lens colors on a police light bar. In the game they look great except when the car gets dirty, then the lens colors become dull. Is there a way to keep the light bar from getting dirty, but still allowing the rest of the car to be dirty?

If this is a model that you made, you could set the dirt layer in the material to a transparent texture.

Without access to the model, i don't believe it can be done.

Like Ceril said, if you made the model you can just apply a blank texture in the dirt spot for that material. If you didn't make the model and its locked there really isn't anything you can do except edit the vehicle.ide and make it so the car doesn't get dirty. I think its the vehicle.ide but I'm not 100% sure