The entire body is painted the base color (medium or dark green) or if you are really lucky, it will come from the factory in all desert tan. Engines are kinda hidden by the engine cover (behind the cab) and I don't remember off hand how they were painted or not. Its been awhile since I've been on one.
Maybe MAJ G could shed some light on this for everybody.
A wise old pilot once told me that its better to be on the ground, wishing that you were in the air, then in the air, wishing you were on the ground.....