Also never owned amps so old. High heat from being class A has me worried.
Maybe you should be somewhat cautious.
A few years back I briefly flirted with the idea of picking up an older local Krell Class A amp only because it seemed like a lot of amplifier for a relatively low asking price, even though I wasn't really looking for a large, heavy and hot running Class A beast.
On inspection, beside the very common discoloration of the heat sinks from high heat, some of the electrolytic capacitors looked like they were bulging a little bit and one had actually leaked a small amount. Several resistors were a little brownish and toasted looking and a few wires had some slight melting of insulation. There was also a lingering burned smell inside. I came to my senses and decided that an older high-powered Class A amplifier probably wasn't for me.
Steve