That is the biggest single "good luck story" I've ever heard of in audio collecting... ultimate "holy grail" gear rescued for free from a house to be demolished. It just doesn't get any better/luckier than that, unless some equally rare turntable and that already-mentioned Paragon speakers had been there, as well.
You are well within your rights and making a lot of sense when you talk about selling these, if they are of no use to you, and you could use the money for other things that are more important to you, and would like to see these in the hands of someone who would appreciate them.
Do think long and hard, though, about whether you will ever want these in the future, because if you decide later that you'd like to have them, after all, you WILL NOT be able to find them again, for less than an arm and both legs plus a testicle, if you know what I mean. Since you play guitar, one suspects you like music. If you like music, won't you want a great system to listen to music on? Systems just don't get much better than these legendary units. And they WILL preserve their value over time. If any gear out there will retain its resale value and even appreciate, it is these. McIntosh tends to retain value, too, but there is a lot more Mac stuff out there, than these rare early Marantz units. That tuner is sometimes considered the best ever made, certainly among the top few. It will always be in demand, as long as there are audiophiles and people with money to match.
Of course, if you do decide to send them to someone truly appreciative, since I can't afford the going rates for these, I'll send you a document hand-written in my own blood during a full moon, promising you control of my soul for a few centuries after my death, in return...
