i have some knowledge with working with fiberglass, and i never want to work with it again. i used to make pool filters, all from moulds. these ranged from very small filters for the small pools, to GIANT filters (about the size of a small bus) for olympic sized swimming pools that went around the world.
i hate to tell you this, but you will need at least a few years doing it to do a body kit that you will drive around. another thing you will need is a catalyst when finishing it of. how do you plan to apply the fiberglass, with a fiberglass gun? i hate to tell you this, but it will be more trouble than it's worth, and it could end up more expensive