After reading your post I was able to contact the PPG rep here in town. First, I think you misunderstood, I'm not covering 36 grit scratches! I've sanded this car to almost glass smooth with 80, 120, and final 220. I can't really detect any scratches, just my anal vision thing, lol. They recommended final sanding of the K-36 with 500-600 before base-coat.
I was told there is no issue with shrinkage for the PPG K-36 and that matter fact, current day paint products are designed to do a project, start to finish in a day, two maximum. Go figure...
Not to derail your experience or knowledge, just that a week sounded like a long time. Maybe if I were laying it on thick, I don't know. Thanks for the quick response, gotta love this place!