oxhadokenxo, paint the outside of the body. Make sure you include a base coat/primer coat as well. Tape up the windshield and other areas you do not want painted prior to starting. If you are worried about the paint scratching off then add a clear gloss finish to your painted car.
If you want to have head and tail lights on your ride then paint those on the inside. For head and tail lights I would suggest a thin layer of paint only to glaze over the area. There are other ways/paints to do this but this has worked for me:)
