Prep is key... Lots of brake cleaner at first to get everything and anything off, lim too... Dig in there, get all the crap out of the little crevices and such. used some micro fibers soaked in brake cleaner n tought spots. Then used one of those silicone bristle disks to "lightly" take off any remaining crap. Don't want to etch anything though, so don't press, I used it in a drill for this even though I have air/die grinders. Especially the top of the SC, like to take all the loose stuff off, you'll see when you go at it.
Final wipe down with brake cleaner then again with acetone. No primer or base, have had great success with Dulicolor High Heat Engine Paint (Ceramic). No clear coat... I can take a pic of my other GTP SC and you'd see the color is still rock solid, no discoloring... I believe clear coat may do that, and I don't want to find out. Prep is really everything. Make sure it is good and clean and paint will stick. The Duplicolor goes on watery, so use very thin coats, no kore than one/two quick light passes over a spot... You'll want to go heavy as it covers nice, but resist the temptation. Light coat will dry to the touch within a few minutes, so its easy to give it a few quick light coats, then medium coat once or twice to finish it off. I think I put 6 good coats on what you see (2/3 light, 2/3 medium) with a minor touch up spray (spot) here and there : )