DIY seatpan question

I was just wondering, for those that have made their own fiberglass seatpans, what would you say your total expense was for the project? Just curious, I have some other methods I am thinking of. Kydex is a plastic that can be easily thermo-molded at home, comes in various thicknesses and might have potential. It gets soft at around 400F, so there shouldn't be a problem as long as your exhaust isn't right up next to it. One of the best things about it, if it doesn't fit right, simply reheat and mold it again. Now as far as how to attach the vinyl or leather to it, I'm still thinking aobut that!