1986 Chevy Celebrity Will Not Start

Engine Mechanical problem
1986 Chevy Celebrity 6 cyl Front Wheel Drive Automatic 108K miles

So the Celebrity has had this problem starting that had been progressively getting worse over 4 month culminating in the car not starting at all.

When I turn the ignition, there is simply one click at the starter, but then nothing.

The initial problem was that it would need more time for the engine to turn over, so I replaced the battery. After this, the car started fine for about two weeks, then the car wouldn't start, and there was no power, but the battery was running hot at almost 14 V, so I assumed it was a connection problem. I cleaned the battery terminals and reinstalled the battery, and the car started up fine.

Then a different turning over issue began where it would click once and nothing would happen. It would start upon the next attempt. Then it would take more attempts for the car to start and now the car does not start at all.

While poking around checking connections, I notice that the ground on the starter that I replaced last year was pretty loose and that the entire starter had somehow loosened. I retightened it, but the same thing happens. The starter clicks once, but then nothing.

I'm out of ideas. What do you think?