I'll use the 69 hood as the plug. A draft angle will be made along the sides of the hood plug using Bondo. PVA will be the mold release along with wax. Strips of balsa will be used as stiffeners or I will use a special type of foam sheet to thicken the final product to make it stiff. Dumas products uses the same material to thicken the hulls of their boats without adding much weight. I use to have a set of glass fenders for a 69 Road Runner. They were solid glass with calcium carbonate fillers and were much heavier than the stock steel fenders. I will post photos after I get started.