Any of you ever make your own Fiberglass parts? Looking at doing some Bumpers for my 70 Road Runner. Plan is to make molds from my steel bumpers. What I'm not sure yet is if the mold needs to be two piece. I'm thinking so, to get it off the steel bumper and then to help get the fiberglass part out of the mold. And, haven't quite figured out how to reinforce the mold yet. Any tips, tricks any of you can share?