FINISHED WITH REPAIR OF POWER SUPPLY
Having received the fuse holder to replace a damaged part, I could now use the power supply that came in the base of cabinet A to power the first drive. It was installed and the wiring harnesses plugged into the J4, J5, J6, J8 and J9 sockets on the supply.
Hooking up the main power cord was more challenging until I found that the bus and tag connectors on the rear were on a hinged panel. Lifting that panel gave me access to plug in the power cord to the rear of the supply.
Using the VOM I verified the +5V, +5V for operator control panel, 12VAC, +12V, +6.4V, +8V and -12V levels. Once these were good, I could plug J4 back in and test a power-up to see the +45V and -45V supplies come on.