You said it had a caulky finish:

Borrow or rent a commercial auto buffer. Buy a gallon of medium grade auto rubbing compound and go to it. Within a few hours, you should be able to buff up that gelcoat to a nice finish. Be careful you don't stay in one spot too long because it's possible to go through the gelcoat and down to the matting. Seal it with a nice, hard Marine silicone wax.

Wyatt