Pits in the metal will not be easy. You will just need to sand the metal in those areas as much as possible to get rid of most of the pits. When I polished my wheels, I used a 6" buffing wheel that mounts on an arbor and chucks up in my 14.4v Makita cordless. This worked really well for me but polishing A/C lines would not require something that large. Maybe a 4" buff would work best for you. Just try to stay away from "loose buffs" as they will not last as long and tend to fall apart in a hurry. You could try something like this:
http://www.eastwoodco.com/cgi-bin/sgin0101.exe
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67 SWB 4x4 - 396 BB / SM420 4 spd
8" lift / 15x14 Welds & 35X14.5 SSR's
Grants Pass, OR
[This message has been edited by Pont (edited March 28, 2002).]