There are usually only three things that go wrong with a starter. Bushings, brushes and the solenoid (especially the contactor). Since the solenoid is clicking that is good.
If the contactor in the solenoid is working you should see a good voltage drop when attempting to start which means current is flowing to the starter.
Then the problem comes down to bad bushings or brushes. A large voltage drop but no spin would indicate bad bushings. Try banging on the side of the starter to see if helps. This might temporarily prevent the armature and stator from grounding and allow the starter to spin. It may also loosen the worn brushes and allow contact with the commutator.
As far as the hot wire, that could be bad connections. The same thing happened to me and the same result as well! Just the starter solenoid clicking. You can try bypassing the starter button circuit by jumpering from battery connection on the starter to the solenoid wire connection to test. Check for corrosion on connections. There should be a wire from the fuse box to the push button. And another wire from the push button to starter.
Regardless, I always bring questionable starters and alternators to a "Starter and Alternator Shop". They have the tools to diagnose and repair starters. All towns should have one, even little Montrose. Regular mechanics replace stuff, they usually don't fix them.
My recollection from driving Santa led me to believe your bushings were bad. I remember a large voltage drop but no start. The thing is, this problem may be intermittent for a long time before the bushings are just "done for".
Anyway, maybe some the great sages will also ring in on this.
Here is nice illustrated tutorial for you.
https://www.howacarworks.com/ignition-s ... or-brushes
Your starter should look like illustration 1.