Nymack66:
Take a look at DURATEC Hi Gloss additive . It's a addtive that mixes 50 /50 with the GELCOAT to thin it out enough to shoot effectively and allows it to dry with a high gloss to eliminate the work of sanding / buffing mentioned earlier. I also heard Patch Accelerator works as well but I do not believe it improves gloss.
I have purchased some of the DURATEC Polyester Hi Gloss additive but haven't shot it myself as of yet. Understand you need a larger tipped HVLP gun to get a good even flow in order to reduce orange peel. I just got my gun from Northern Tool recently had haven't had the time to play yet.
Here's a cheap HVLP gun with a tip size that I have seen reccommeded for shooting gel coat.
http://www.northerntool.com/webapp/w...9459_200319459
Here's link to more info on the Duratec product I mentioned
http://www.duratec1.com/dp07.html
Kamikaze