Here is a scan of the schematic from the HV section. There is one change - the previous owner replaced the flyback some 20-odd years ago and the instructions for the new flyback state that pins 4 and 10 of the 6KD6 are to be grounded.
Holmesuser01 - thanks for the suggestion about the damper tube. Is there a way to test that theory or is it just a replace-it-and-see type of thing? There's a guy fairly local to me who sells tubes; that's where I got the replacement horizontal tube. I'll have to give him a try. If nothing else, I'll have enough spares to last me for quite a while
To all - Thanks again for all your help on this set and with cataract removal. I'm still getting my feet wet, and at times these problems can be quite daunting. Hopefully someday I will be able to be one of the ones providing the help!
Jim