Temperature sending unit problem.

68_Valiant_Wilson said
Could it be that I just got the wrong sender?

Could be.

duralast

Duralast = generally garbage.

TU22

May or may not be nominally correct for the application. If so, may or may not have the correct resistance range.

It came with no red tape on it.

That doesn't matter.

have been told that if it doesn’t have any tape on it it will not function properly

That's not correct.

I really do not want to pull out the dash to test this

Odds are very good that your options are to pull the dash and fix it, or leave it unfixed. This is part of what goes with driving an old car: you eventually have to fix stuff most drivers never have to think about.

I’m afraid I’ll never get it back together right.

How come? Instrument cluster removal and installation isn't terribly difficult.

I’m really kind of clueless at this point.

No, you aren't; you've been given lots of good clues here in this thread. Now you just have to choose to pluck up your courage and follow them.

I have a connection when I test the battery ground and the sending wire so I’ve ruled out bad wire.

No, you haven't. You need to make sure there's no significant resistance in the entire length(!) of the wire that runs from the sender to the gauge. That means pulling the instrument cluster.