The mod is in and seems to work. There is more picture information. My 7 inch tube is dated 1943 so it takes a bit to wake up (it's older than me, but not by much
Now I'm looking to try it on my Zenith Square tube. It looks like it's going to fun.
By the way, I looked at the TM21 (hope those #'s are right) monitor.
Now that's a bunch o goodies in a cabinet!