Greetings kind people. I am in the middle of a repair on a Peavey Session 400 from the 70's. So far I have replaced a resistor in the Reverb send/rec section and re-attached two components where one leg had lifted off the PCB. I am getting output now but I have an issue in the power supply rails to the output transistors. I am getting a solid +50 vdc on one rail and -50 vdc on the other. I can signal trace an input signal and 50vdc  off of 5 of the 8 sand box resistors in connection with the output transistors. The other 3 have 104vdc and a buzz. I pulled one of the output transistors (5 seem to be working fine) and tested with diode checking and it appears to be ok.I also have no signal at the send of the reverb circuit section, but the return and tank are ok. I'm not that experienced with SS power section diagnosis, so I'm hoping someone here might give me some advice on where and how to start best. Thanks for reading/thinking etc - (I have a schematic from Peavey BTW)