While working on this set, I caught some whiffs of ozone. I was running by B&K 1077B which has a known corona issue so I've been ignoring it.
A few days later my 1077 was off and the ozone smell was even stronger and I heard some hissing so went investigating. I popped open the HV cage, powered up the set with all the lights off and carefully looked around.
Sure enough there were faint blue streamers around the doorknob cap mounted under the 1B3 HV rectifier.
Turns out it was black with fine dust particles. A little cleaning with mineral spirits took care of that. I made sure to dry it thoroughly with a heat gun on low before powering it back up. No more ozone
Just one issue remains - the vertical lines on the left side of the screen. I've tried swapping the damper tube, adjusting the hor. drive and hor. linearity and hor. width.
None of that had any effect so I'm going to check the 47pF the mica cap inside the yoke.
One more thing - I'd been calling this a 16R12 but that's incorrect. The 16R12 is brown bakelite while this one is a black 16R11.