The hood sat in the sun most of the day yesterday, so I thought I'd try to wet sand.........good to go! For this step in the paint/body I'm using 220 on a stiff foam block. You can see pretty quickly how thick and rough the buildup was on that primer. The goal at this point is to block sand down to a smooth primer finish. It's ok to still see some dots of guidecoat, and even some color from UNDER the primer. The reason being, after any filler touch ups the whole thing will be primed again. Then blocked again, then of course a few coats of paint on top. There's still plenty of material going on to cover everything well. You don't have to go through all of this........if you're satisfied with "good enough". But if you want super slick show style paint.......you need to go through all these steps.