Just out of curiosity, I stripped some of the old paint off of my truck in various spots using a razor blade just to see what was underneath. My guess is this truck was last painted in the 80's. Metallic blue BC/CC. Regardless of where I stripped the paint off I find the same thing. Little spots of rust everywhere between the primer and the color coat. Nothing showing through the color coat though. Any thoughts on what would have caused this? Polyester primer soaking up moisture before the color coat?