Okay, I'm about halfway through my first cut of block sanding the PPG K36 surfacer on my car. So far I'm very pleased. I have a few (not too many so far) high spot where I sanded through to bare metal. My plan is to seal the whole car with a coat of reduced PPG DPLF epoxy primer before spraying color. My assumption is that this will also suffice to re-prime those few shiny spots of bare metal, but my combination of paranoia, and lack of experience make me think it wise to make sure the brain trust agrees with this. Here's a couple examples of the spots I'm talking about - gray patches are DP50LF primer base coat but you can see two roughly dime-sized shiny spots.
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