Advice on dealing with a focus element issue in a 21AXP22

[Electronic M]

So I've been working on a CTC-4 I got from a member here. The set came to me making a raster on original caps.

It had some arcing noises. I eventually discovered they were from the CRT when unplugging the CRT hv lead caused the noise and unstable 1.2KV DC read on the main B+ line to go away and stabilize to the rated 350V DC respectively.

I tried to discharge the HV then pulled the shroud and got a good bite off the CRT anode cone...I then realized the HV connection spring was missing 1/3 off its end, and mashed against the insulator (thus to reach the CRT it had to arc)...Folding it out to make contact caused it to snap off so I robbed the same part off of a spare CTC-4 CRT insulator shroud I have...That fixed the arcing and I could get the set to pass lousy color video with lots of issues with HV stability etc.

With low HV I could get a full screen focused picture that would intermittently be part way swamped or completely out of focus by hum (seemed to be synched to vertical most of the time, but occasionally would roll or be gone for 30sec).

Once I recapped enough to get stable HV I began to realize I can't get focus with the HV normal. The focus seems to be stuck WELL under 1KV, and was loading the focus rect tube down to 2KV through the series resistors.

Now at the end of the night I confirmed that disconnecting the CRT socket restores focus voltage to normal 3-4KV...

The CRT does not show signs of gas (if it did I'd expect the HV to arc to the focus and some neck glow).

I'm probably going to continuity check the focus tomorrow. I'm pretty sure my tester doesn't have a 'remove focus shorts' setting. How should I clear the focus element short I expect to find tomorrow?