Congrats! Nice to see a Portable brought back to life. I'm working my way toward dragging mine out and seeing if it still works.
It makes sense to me. If the opamp's output is way off, yet everything else checks out, then it must be toast. I did swap Q207 at the same time, but it tested good once I had it out of circuit.Never once have I changed an Op-Amp and it had actually fixed that. Makes me kind of hesitant.