So I have the body work done and in primer. Blocked to 320. I can't find rolls of paper for my durablocks past like 400. I feel foolish asking this but is most of the blocking past 400 grit done on a short wet sanding type block? Do I just buy standard sheets of sandpaper or hook and loop or PSA? Is it a bad idea to buy hook and loop DA discs and using one of these to do the final sanding before basecoat?