In a 32A42 and 27A32 D404 is 9.1 volts.

Look for a filter across it, this should give you a clue. My database
only has a few entries, but the symptom was the picture off center to
the right. If you have a dead set, this may not apply, but it's thew
best I can do right now.

Also, there is a root cause for that failure. I can see the resistor
going bad after X years, but if the zener is shorted, the voltage to
that circuit was too high.

If the zener is in the power supply in your case, you really should get
a print. You might try to borrow one or something for a 20" set, the
cost might be prohibitive due to the cheapness of the unit. From what I
hear the models I mentioned are manufactured by Orion.

JURB