I know how to lay fiberglass...but not custom molds. If I was to do custom interior parts, I'd leave it to the pros, but that is just me.
I've done a few exterior repairs with fiberglass, but thats about all the experience I know with fiberglass.
Sorry I couldnt be of much help there, but you might want to try your local bookstore. I found lots of great info on bodywork and custom work.