Thanks for the kudos, Bob, much appreciated!
As for spotting the transformer problem, Deadfish, I originally thought it was OK; it tested OK as far as delivering power, but when I took the bells (covers) off to paint them, one could see the unit had been severely stressed at some point. There was a considerable amount of varnish that had melted and the insulating paper was charred from overheating in several spots. One did not need a trained eye to see the problem.
While the transformer did work, it would have been foolish to re-use it. Complete failure could have happened at any time wish disastrous results - shock, fire or taking out other components in the amp. It just wasn't worth the risk.