After putting this off 2 months, I got back on the horse. Our youngest daughter also had our first grand baby (grandson). I'd rather hang with him than sand airplane pieces. Anyway, it was beyond time to try the new Harbor Freight spray gun. This is when I learned that the gun was my problem. Once again, this isn't that hard. Unfortunately, I didn't touch the plane for 2 months because I dreaded this and felt ignorant not knowing what the problem really was.
With a gun that works, the primer went on really well. A buddy told me that he puts it on pretty thick because most will be sanded off, so don't worry about runs. I do have a couple of runs, but overall. I'm very pleased.