Ive got the mold made for a hatch gutter. I need to make 4 gutters this size. 2 questions. One is reg silicone / gulf wax ok for release agent ? Second, would it be easier to lay the fiberglass in the mold trough or on top of mold so to speak. Need to slick up whichever side would work best. Either way will work fine for my purposes .My first go around with making a mold , im a jack leg fiberglass man , heavy on the jack leg. Trying to keep it stupid simple ! Thx ahead of time.