Dill you are correct. Took it apart today to get a picture for my service center. So I turned the screw / cam and watched the needle going up and down on the meter that I hadn’t touched. The offending meter would only go up. So popped out the screw cam and put it in correctly now the needle can be adjusted up and down.
It is too bad the old MC7200 glass wasn’t in stock when it was being serviced because replacing it and the bulbs is a lot of work. I remember a while back someone was not happy with the $300 charge to change the lights. It is worth it especially if you have to change the glass. There was a lot of parts glued to the glass.