I can't argue with success, but I've gotta say, 180 grit scares me.
When I dress out the pits in the cap where the piston rides, I use Micromesh MAYBE starting at 2400 grit for bad damage, but usually 4000 progressing to 8000 grit. It's slow work, but having a mirror finish for the piston land has stood me in good stead with old corroded regs. I worry a little about residual scuffs from such coarse grit becoming an abrasive surface for the oring. There are those that say that those scuffs are good grease-trapping reservoirs to maintain a seal, but I think smooth is better.
