What do you know about "circuit analysis"?
I have too many years as an engineer to give you a simple answer to what some may consider a simple question. I try to start by establishing (as much as is practical) WHAT is wrong, AND what is right, and any other salient facts that I can establish. Next comes a comprehensive analysis of this datum, including WHERE these conditions exist, HOW and WHY they might have occurred. (WHO & WHEN are not very important for this case.)
The parts you replaced at the burnt spot (TR20,R46,R56,R58,R68&R70) are all p/o TR20's circuit, and it is easy to believe that something went wrong with TR20, and took the resistors with it. Throw in the failure of TR601 & R72 and I wonder if something else went bonkers and led to secondary failures of these components. You could test this out by replacing all these parts, firing it up and wait to see what happens . . . .
My approach is to check out the circuits and components that feed TR20 and TR601, hoping to find a primary fault and fix that as well.
Bottom line: I cannot answer your question without asking you a LOT of questions. AND, since I still don't have my G-6700 repaired I am probably not a good one to be giving you suggestions.