Captainkirk's Duster project

Are you wanting a cheap gun to shoot the engine compartment or a good gun that will do the whole car?

Big difference, just to shoot he engine bay and do door jams etc the cheap purple harbor freight $15 one will work fine.

For a nice overall gun I have a LPH400 Awata, not cheap, but the paint jumps on a vehicle with no effort, worth the money, but they are around $500, but the paint lays down so nice.
I haven't thought far enough ahead for the external paint yet. I'm hoping to be able to pay somebody to paint the car this time around, but available cash will dictate that down the line. But the engine bay needs to get shot before the motor goes in, so HF will probably have to do.