Me, I'd leave the meter in - it was a mod kit from RCA, and many shops had them. Our roundie jig was an old metal cabinet set, and we just hung a HV probe in the back, but the RCA meter would have been much cooler. Yes, the mounting location is right by what RCA published.
The kit was part number 10J110, and was a retrofit for all RCA jigs made before 1968, and had instructions for the Tele-matic jig as well. The RCA portable jig(s) already had the meter.
http://www.americanradiohistory.com/...#search=%22rca jig%22