
Well rats...
tried to do a basic convergence on it and found a broken coil, the core is broken in 3 pieces, and the paper tube is ripped, someone made a big mess of it, I DID find a replacement.
edit
well
pics do say a lot
https://i.imgur.com/d2JYqXT.jpg
https://i.imgur.com/msdSFRu.jpg
And I did confirm that HV does drop down when brightness is turned up, even with the cap off the shunt regulator.