[Yamamaya42]

Latest status update.
When I first got this set, the cover was off of the HV cage and the 2 HV rectifier tubes were out and set aside, indicating someone was trying to debug a HV problem and gave up and left it to sit for untold years.
This would not have mattered if it worked or not, since the 16FP4 was worn out and most likely could not show a picture anyway.

The flyback transformer was in a very questionable state, partially to exposure to the elements and the others due to age and the old wires to it being old and full of splices, the old one may or may not have been OK, but since I had a NOS one, why risk it.

With the flyback out, a test of the horizontal oscillator seemed OK, but a bit of a mystery because I was not sure where it was getting power from w/o the flyback in circuit, this turned out to be VERY leaky paper caps, that when replaced, the horizontal oscillator stopped.
A quick bypass of the area to power proved this, good strong horizontal oscillator.

So last night, I started to replace the FBT wiring with new 600v lines, staring with the #5 line to main bias, and #4 to the plate of the damper, link 4 & 5 together, and power up, then the horizontal oscillator SHOULD have started, this did not happen...
Odd, why?

Checked pin 5 of the 6W4GT, good positive voltage, then pin 3, cathode, negative 60v... that aint right!

Not right at all, grabbed the one other one in my hoffman set, BINGO, positive voltage on the cathode, and the horizontal oscillator started.

The bad 6W4GT is most likely the original cause of the HV problem with the set.
New one on the way, plus new 6GB6GTs.
In the meantime will replace the other FBT lines and get the new one in, and replace more caps.