Apparently the nomenclature I used earlier regarding the rotary switch for your cathode current meter was incorrect. A shorting switch and a make-before-break switch are one and the same. I was sure a shorting switch is one that cumulatively shorts adjacent contacts together as the switch is turned, but that's not how manufacturers are presently describing them. In fact, during a quick search, I couldn't even find that configuration.
Anyway, I just wanted to point out a switch on eBay that would do what you need for the meter switching. I stumbled across it while looking for something else.
Buy Chinese. Bury freedom.
Edits: 06/24/17This post is made possible by the generous support of people like you and our sponsors:
Topic - Ping: DAK - Triode_Kingdom 14:57:59 06/24/17 (4)