Using sprayed in FG could be. . .risky. I've had FG cary body parts explode on the highway from rocks. It makes a lovely mess.
If you wanna go FG all you need to do is get a mold fabbed, put a liner down, lay Fiberglass cloth(
Fiberglass Cloth in bidirectional weave) coat in resin and fixative and sit and wait. It heats up a little you wait 45 minutes pop it out sand, smooth paint bolt.