I sanded the inner fenders 180 this afternoon and you can really see the low spots even without a guide coat. I'll fix up the worst of them and reshoot with the primer (it can go over bare metal) which will take care of a few spots where I broke through. I should be good to sand everything 400/600 then. I might even just use red scotchbrite on the lower sections and frame rails. As I said, its good practice before I hit the important panels. :) I'd really like to get my engine broke in on the test stand and get it into the engine bay after brake lines are installed.
