Mike very helpfully includes in his package a replacement cap for the one at cc33 which is working in a 30 volt circuit but the cap Gottlieb uses is rated at 25 volts. This is mentioned in the pinrepair guides, and the other day I had tried to get the proper cap at Jaycar but they didn't have it in stock. So before installing the nice new amp, I replaced that cap.. .. Then it crossed my mind that it was the 30 volt circuit that had the issue, and when I tested the old one out of circuit it was a dead short - and the continuity I'd noticed earlier at the amp was gone. So on a whim I thought I'd try the board with the new cap.. .. And it worked!!

I did have to replace one other chip as the board was making off sounds, but it's working perfectly now.

I've had a chat with Mike, and he's still keen to see this tested, so if anyone out there has the need to give this a try and will post the results here, let me know and I'll mail it to you to try out.