I used this technique on my '52 GMC Pickup when reassembling during my frame-off restoration (one slip and the paint chipped when reinstalling sheetmetal):
1. Fill chip with a little paint at a time over a period of a few days, until the paint is built-up proud of the finish
2. Lightly rub mound with WET 1400 grit wet sandpaper (available at any good auto parts store). Because the sandpaper is so smooth, this will require several small pieces and patience.
3. Once the touch-up is level with the paint finish, polish with very mild compound
(I used Maquires Step 2 polish with excellent results)
4. Complete with a few coats of wax
Good luck! I'm doing the nose of my ricochet silver ssr this week.