TECH: G07 power problems

Please pardon this lengthy explanation:

I've been trying to fix a problem with a G07, but I made things much
worse in the process. The monitor was working okay, with some slight
horizontal image shifting occurring. The H-frequency pot seemed to be
the culprit, so I swapped in a v-hold pot from a different monitor and
things went very wrong (I'll freely admit that I didn't check the
ratings on the pots, so I don't know if they are compatible or not).

Anyway, when I hooked it all back up and powered it on, there was some
crazy arching from the anode across the back of the tube. I turned
everything off, re-seated the anode cup and powered it on again. This
time, the arching started jumping across the yoke. I turned it off
again, pulled the chassis, put in the original pot, and hooked it back
up. When powered on, I get no image whatsoever now. Power is getting to
the chassis, but there is no signs of life whatsoever. The game plays
blind. The fuse checks out, but there's no power on either side of the
big resistor on the side of the chassis. I swapped in a known good
chassis, and get the same problem. No power, no image. I would imagine
that even if I cooked the tube, I should at least hear SOMETHING from
the chassis when powered up. But no. Not even a crackle or a hiss. I've
tried disconnecting the degausing coil, but it doesn't help.

Could I have fried the isolation transformer somehow? I've tested the
current going into the chassis, and it seems high, but it's there. If
the voltage was too high (say 150v), would the monitor power on and
then shut off right away or just not turn on at all?

In conclusion:
Game plays blind.
No image on screen. No power reading at the resistor.
Tested with known good chassis with same results.

Any suggestions?

.

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