I used a hot glue gun to to stick the plate onto a piece of aluminum angle so that I could hold the thing in the vise. It's an old percussion shotgun lock that was pitted. I used an orbital palm sander to get through most of the case hardening so I could file the pits out. The palm sander doesn't dish out the holes like what happens when someone uses a buffing wheel for the job. It shouldn't be to hard to clean up the glue since it seems to be water soluble.
