Originally when I bought the car only the speedometer, alternator, and one side of the dash lights worked. I had the entire gauge cluster replaced and it actually made the problem worse, the other gauge cluster I got had a bad circuit board one one side and the gas and temp gauges were both pinging out on the other side. I put in the old circuit board back in and got the dash lights and the alternator gauge to work on one side, I swapped in a different gas gauge and now neither of the gauges work at all and the dash lights still don't work.
The speedometer was making a loud ticking noise like if it was trying to work but unable to, I took it out and found a bunch of sludge in the gears, cleaned it out but now it won't even try to work at all, I thought the connection was unstable in which I bought a new circuit board and got a better speedometer cable, the connection is stable but it still refuses to work.
I'm honestly at a loss and out of ideas, my guess is either the wiring somewhere else is bad or somehow the gauges are bad in another way, hoping that someone can give me an idea of what to do.
Well when you're dealing with old stuff like that you said you replaced the dash unit but it was obviously a used unit and it could be bad too. Now years ago there used to be guys who would repair those things but they're long dead now. There are relatively simple though you can trace all the circuits on it see if something's shortened out maybe a solder's come loose or something
Check Hemmings for services that may be able to rebuild your dash panel.
Your speedometer head is mechanically operated. There are no speed sensors, it's as simple as spinning transmission drive spins a metal cable. There are springs and probably a couple magnets in there which do the speed metering. Any gears wpuld be related to the odometer. A pro needs to figure out what's wrong and service it. I had the service done by D & M Restoration on my 1979 Pontiac. I wouldn't really recommend them. They've had my cluster 4x under warranty and my dash clock still doesn't work for more than a few hours.
Likely the springs have worn out or are broken, which is causing the loud clicking noise and erratic needle movement.
Did you do the logical thing and change the lights inside the unit? If it's anything like my Pontiac, which is 15 years newer, there isn't really much in the way of internal circuitry, at least not for the lights. There's probably a plastic "foil" type thing on the back with copper ribbon laid on it. The bulbs twist out the bulbs pull out like any other light.
If your car does have this style of circuits, you can check continuity on each ribbon with a multimeter. If copper ribbons are damaged, you may be able to find another backing.
I can spin the speedometer manually with my hand, it moves freely and the odometer goes up, mechanically it works fine, it just doesn't seem to be getting power now, compared to how it was before I removed it to clean the inside out, I suppose I could try going back to my old speedometer without the odometer, which I know for a fact works and would be a sure way to test if you unit is getting power at all.
And yes, I did change the lights, but I do have some other extra lights I could try out too.
I can spin the speedometer manually with my hand, it moves freely and the odometer goes up
Then the speedometer cable is probably sticking and binding up due to wear and nearly 60-year-old lubricant. That could make a loud ticking noise as you described.