I primed part of the right wing over the fuel tank and the entire outer right wing panel. This coat on the outer panel was applied in three layers via roller. Most of it will be sanded off for smoothing the surface. I have found that the Advantage Urethane Primer Surfacer dries well enough in about 10 minutes so that I can add another rolled coat. The left flap was also worked on on its top surface extensively to get it flat enough to paint.