Just got a refurbished one, and Was thinking about painting it red w/ a chrome cap to sort of match the rest f the car rather than leaving it the grey color it currently is.
Is that totally dumb?
Not at all. If you do a nice job I think it'll look great. I always like it when people show some attention to detail on an otherwise overlooked part. Go for it.
I usually put a clear on just to keep it from rusting but every time you pull the cap off needs to be a surgically clean procedure as brake fluid will eat the paint right off. There are fluid resistant coatings; check them out... it seems I remember seeing some at Eastwood.
just go to your local home depot or Lowe's and get some Red Devil (or any brand really) Appliance Epoxy paint, brake fluid won't eat through the epoxy nearly as bad. VHT also makes some epoxy paints as well that you can order from summit or jegs if you can't find them locally.
I bought some auto paint from the sherwin williams auto store (matched to the car's paint). I actually just used a model hobby type of airbrush and sprayed it on. Then did the same w/ a couple coats of clear.