Cant see the neck board very well
take it off the tube..
I was going to point out components on the board
as we work on it..and i can match up the board with the schematic...
You will need to take off the metal sheild..
Cut the glue on the tube holding the neck board on..
I ask you to desolder the GK pin..
If you cant find the pin take a picture of the pc side of board..
To see the GK pin, some are marked,otherwise i was going
to check the schematic to help you find the pin...
One version board use,s discrete components for video amps and other uses
a Ic...for video amp..The Ic is at the top of neck board.
I assume you dont have a CRT Rejuvenator?
Can't clear the short without it.
If the picture is still all green after removing the voltage to the
cathode then the tube has a short..If the green is missing then
parts on the neck board need to be check..
A Tv shop should have crt tester you could ask them to clear
the short for you and pay the labor. Good Luck!