Yes, placing the screwdriver within an inch of the anode lead should produce a nice light show if you have healthy HV. Perhaps a little closer if the HV is weak.
If you disconnect the anode lead from the CRT and it's just dangling there, as you place the screwdriver close to it, it might actually pulled the lead toward the screwdriver.
Doesn't the HV go thru the horz windings of the yoke before getting to the CRT? I know it's less likely to have a yoke fail than your HV module thingy, but it would be a quick and simple to check the yoke connection and also put a meter across the leads for the horizontal winding to make sure there's nothing open.
Also... you mention a leftover bumble bee... where is it? Could this cap be the problem? When I recapped my Halolight years ago, I didn't get any HV at first. Turned out, I missed a small paper/wax cap... something like a .0047... was hiding under another component. As soon as I changed it, HV came in just fine.
I used to
purposely check the HV with a screwdriver if someone was at the house while I was working on a set... and do some mad scientist laugh while doing it. I recall my younger brother's eyes get wide one time when I did that... and he walked out of the room saying
The hell with that... I'm outta here!! My brother was not a fan of playing with electricity.
