As far as the airbrush work, I usually do that last after the base color has been applied. I usually use base/clear when I am doing graphics, so that would mean sanding the clear coat on the doors and re-clearing once the graphic work has been finished up.

If I were doing the airbrush work, I would prefer the doors off the cab so that both doors could be worked on at the same time and I could position as needed on the work bench.

Dave Brisco
Dangerous DesignWorx