Dean, I preface this with "I'm not an expert", but I do know that if your paint shop hasn't got experience with dealing with fibreglass gel-coated finishes and their prep, you might want to shop some more. I would not want to be telling a professional what products to use and then have trouble holding him to quality of work later if there was a problem.
Soon an expert will chime in and tell you PPG K200 or something...