Easy-Off oven cleaner.
Mark:Yes, I said "Easy-off Oven Cleaner". You need to find a nice warm day (cannot pre-heat the oven) to work best.Spray it on and let it sit for 10 min. (about enough time to sip your first beer). Then get a medium stiff brush and scrub. This sometimes takes 2-3 applications (2-3 beers).When all of the paint is removed you may notice a yellow cast in the gel coat as well as a raised area. It is usually best to let the area age in the sun, but that is not necessary. Before you apply the vinyl, be sure to wax and clean the entire area. Actually a good cleaning with something like the Island Girl Pink would be good at this time.