Personally I'd fit a buffing wheel to a bench grinder and hold the part in a handheld vice of some sort (pliers, vice grips, threaded rod on a stick...
I think actual buffing setups are slower speed and larger diameter then most home/hobby ones. I believe this is to allow for heat dissipation. Also plan on holding the tool or holding the part. Holding both is for desperate last minute touch ups before shows
Matt