I have the general idea on how to fiberglass, I know you have to lay the fiberglass cloth over the area i want to fiberglass, then lay a couple of coats of resin over it, but do you sand it once it drys or am I missing a step, do I have to always apply the clothe if i'm sealing the inside of the box. how long do I wait til I can began to sand. I'm looking into making custom door panels and A pillars and and making custom boxes. If I'm going to do something, I want to do it right the first time. I think I pretty much get the concept, I just want to see what I'm missing. thx