tips for spraying primer

Matthew, do you have a picture of your car as of right now, so I can see exactly where you are with your bodywork/primer? I'm more interested in if you've sanded through to metal in any areas, than in seeing the pinholing itself. The whole idea of high build primer is to build up thickness so you can sand off the high areas and reveal the low areas. Your pinholes are low areas, and if not properly handled, they WILL come back to haunt you down the road.
What high build primer are you using?