I fixed some small rust spots with POR 15. The POR-15 seems to have worked great. My problem is with the topcoat.

I sprayed several coats of topcoat without problems sxcept for some runs which I caused. So I figured I'd wet sand and then spray again. After wet sanding I wiped down with prep-sol and then enamil reducer (this is the same procedure I used for the first topcoats which had no problem). When I sprayed the next topcoat the paint crinkled in several spots. I figured I didnt wait long enough after the wipe down. Waiten till the next day on another spot same thing. Sanded down again and cleaned with degreaser, and rinsed with water, and let dry overnight. Problem reduced but still there in a couple really small spots.

Do I need to strip the topcoat completly with laquer thinner and start topcoat fresh? Any advice from people who have painted previously would be great.

Paint was custom mixed for the car by local auto paint store and put in spray cans.

Thanks
Paul

Not clear what kind of paint you are using but sounds like enamel. It needs to be quite dry - days even weeks - before you can respray. Sounds like you might need to start over to get it right - and you might want consider switching to laquer - not as durable but generally easier to get on and to "work" the finish.