60 years can be a long time for a panel without any TLC.

See Rust in Panel

Today I plugged my Alexia into a power outlet 20 inches from the electrical panel. 14 gauge wire on a 15 Amp arc-fault breaker. I watched it heat up and the PID started cycling the 11.3 amp heater. After an hour I pulled a shot and the pump did not slow down or speed up with the PID flickers. Some troublesome lights in the house did not flicker either.
Voltage min max variations were about 2 to 3 V.
Makes one think that a long run to the espresso outlet in the kitchen, 100' of 12 G in my case is a part of the problem.
So I'm declaring the Alexia the workshop espresso machine now.
Done deal,

Dave