I'm about to do this. Mike at Rentech kindly showed me how to get the calipers off. It's only two bolts on a 172. The pads then just unclip. Should be easy to work on then. You can get the paint from Halfords (Folia Tec) and that includes the cleaning liquid. Like others have said, get a wire brush too. The better your preparation and cleaning, the better the result. Red is the classic colour, but black or silver on your car would look good, and be a little different. Get all calipers off and prepared first, as the paint hardens very quickly, 2-4hours.
Doing mine next week when my car's off the road.