Later, to check my work, I'll airbrush on Tamiya water based acrylic flat black. This is a good paint to use to see if any bodywork will show through after the paint is dry. You can then take ammonia (Windex will do) and wash off the paint before you actually primer the body again with automotive paints.

I'll tackle the roof trim front and rear next to make them more realistic........and to also not be buried under the multiple coats of primer and paint.