About cleaning your gun.
Is your gun a gravity feed? If so there is probably a small filter under the cup (hopper). Before you start shooting the finish coat, get some gun cleaning brushes. Unscrew the cup from the top of the gun. Most of the filters have a small white plastic tab. Remove the filter, then using some acetone scrub all your parts using the brushes. Replace the small filter with a new one and reassemble. Often when you are spraying primer those filters can get clogged up. Then you have problems when you shoot the finish.
Practice shooting finish coats on some scrap sheet metal before attempting your truck. Finish coats are thinner then primer and are harder to spray without runs.
Is your gun a gravity feed? If so there is probably a small filter under the cup (hopper). Before you start shooting the finish coat, get some gun cleaning brushes. Unscrew the cup from the top of the gun. Most of the filters have a small white plastic tab. Remove the filter, then using some acetone scrub all your parts using the brushes. Replace the small filter with a new one and reassemble. Often when you are spraying primer those filters can get clogged up. Then you have problems when you shoot the finish.
Practice shooting finish coats on some scrap sheet metal before attempting your truck. Finish coats are thinner then primer and are harder to spray without runs.