I've painted a few cases, bit I've had problems with the paint easily getting scratched off moving it around or taking panels on and off. Is there a clear overcoat that works to protect the paint and can be fed through an airbrush?
Depends on the paint also, I tried to clear coat certain sections of mine (i did a flat black) and it made it extremely blotchy and it was actually ruining the paint, like eating through it. I let the paint dry overnight too. If it's just regular gloss colour, a clear coat should be fine though
There is some 2-components clearcoat around (i believe poly-urethane coating), which should be crazy strong!