I'm sure some of the experienced painters on here will have their recommendations Barb, but I have been buying the gravity feed guns from Harbor Freight and getting good results from them. They are normally about $39.95, but they went on sale for $ 9.95 so I bought 5 of them. So far I painted everything on my T except the body, and everything on my Son's T except the body. Never got any runs or other problems. I had a $100 Sears gun and the HF ones did as good if not better.

As for your problem, you are going to have to sand down and start over. You chose a tough color and paint to start with, reds are sort of translucent and hard IMO to get even.

Don