Was helping my son check his speedometer as it wasn't working. We had already checked at the tranny so I was gonna check the connections at the gauge. Now the fuel gauge is inop when I put it back together. Also the alarm for the key is on constant, even when the car is running. Anyone ran into this issue?

Check all your fuses , including those in the "convenience center" .

I say this because somewhere here I recall reading a thread where a blown fuse resulted in the key buzzer sounding continuously , I just don't recall which thread it was ....

Do you mean you removed the cluster to check connections? Sounds like you damaged the printed plastic circuit on the back of the cluster. They get brittle with age and the contacts like to lift off the plastic, ie they don't like being disassembled and reassembled. If you don't get it lined up just right, it's easy to break the loose contacts.

If you had the cluster out, start by taking it back apart carefully, and inspect the brass/copper contacts on the circuit. If they're just bent, you might be able to carefully bend them back. If the contacts are damaged, you'll need a replacement cluster, or circuit from a donor car.