Upon checking the insides I noticed that one transformer had shilac colored fluid....possibly leaking on its bottom.
@rocky1313 The filter capacitors in the power supplies of these amps are so old there is no way they are any good. It would be a mistake to power up the amps, even slowly, until they have all been replaced.
If you do not heed this warning, you may well find that the power transformers have failed and that will really cost a lot! The power transformer is the larger of the two black metal things at one end of each chassis.
Its worth it getting the filter capacitors replaced!! Any competent technician can do the work. The capacitors should not be that hard to find since CE Distribution has been stocking and manufacturing them specifically for older tube amplifiers.