Just bought this today (porter cable 7336sp) and was wondering what the foam pad that came with it was for? as in, do i place a bonnet over top or foam pads? Also came with a 5 in? backing plate. I own a new car which i have taken very good care of so far, no flaws or swirls that i can see , gets waxed at least once a month, so my next question is what kind of pads do i really need? Paint on this is in great shape! Just want to keep it that way!