Don't think you need to wet sand, rubbing compound should do the trick. Not sure whats in the Buff Magic, it may be just a mild buffing wax or polish. Go to auto parts or car paint store and get rubbing compound. You will need a good buffing pad to put on a drill or buffer. I would try this first before wet sanding, rubbing compound should take off oxidation. Be careful on sharp 90 degree corners and other pronouced areas. You can put a piece of making tape over those areas, then hand rub later after main body is done. Used to work at a large body shop. Hope it works out for you.
2002 Moomba Mobius V
Rick