Finished repair a couple of week ago. Thought I would update final repair. Amplifier worked but had a odd 3mhz oscillation on the output. After a lot of head scratching a talk with Bill we added snubber caps on the drivers which were replaced. This did take care of the problem. The new transistors of today are of higher performance and higher bandwidth gain then the old transistor, so you have to degrade or reduce the bandwidth to not introduce the reproduction in this case of the power supply ripple. Nice to know now and makes sense. Amp is stable and really a nice product with its matching dual 15-inch cabinet in folded finish. The customer got this at a garage sale for 50$ and seems pretty darn happy now.