Ok, coming off pin 2 R759 do you have 20V on both sides of that resistor...?
What voltage is on center pin of brightness control..?
What is on R733, either side...?
You are running the set with what no HV...?
No one is asking you to lift every cap, just ones that may lead to an answer...
Sorry you are the one stuck doing it all.....
Found cool little website while looking up 12by7a to be sure pin numbers are
right.... Pretty neat.....
http://www.intio.or.jp/jf10zl/index.html
.