Yep, that was it
Had the chassis on the bench, so on my lunch break I jumpered the connection, and used the variac to power it up.
It's sure an improvement from where I was when I had a picture last, but it's still not right. Contrast control does nothing, and neither does width. I can get it wider, but then I have to max out the horizontal drive and the whole picture darkens up in the center. Focuses fine. Not very bright, but I did notice that the picture is getting better just with tweaking and use, as everything is beginning to "wake up".
Getting there, getting there
. Think it's time to re-test tubes before I go further. One candohm was working but was out of spec, so I'll place that on my next Mouser order.