[lbperry]

When we painted my car, we used single stage paint the same color as my final base color as a primer. This did two things: 1)the gloss in the single stage made it easier to block sand, the low spots still showed gloss, and 2) the multiple coats of the same color insured a uniform color and assured me that I was getting the final color I wanted.
Just my .02.
Good Luck