LOL
I spray painted mine, and they've held for quite a bit with no signs of chipping.
As you may or may not know the caps pop off rather easily. Granted, when sanding, you may want to keep them on the mirror, so as to make the job easier. Once you start painting, though, you'll want to take them off.
Sand until smooth, clean, spray 1-2 coats of adhesion promotor, spray 2-3 coats of base, wet sand slightly, spray 2-3 coats of clear, wet sand, buff and polish. Should take more than a couple hours, not counting letting the clear dry over night before polishing.
I used the adhesion promotor in a can sold at Autozone/Advanced, though you may want to look at the Bully Dog one. Apparently, it's pretty good. For base coat, I used the duplicolor spray can. Same for the clear. Overall, cost around 20 bucks to do over the weekend (I already had sandpaper).
OR, if you don't feel like painting it yourself, sand it smooth and take the caps back to them. They'll probably do it no problem. That's what a lot of people do. They get it done at places that, before they had sanded smooth, wouldn't even touch them because of the texture.