Confirm my fuel gauge issue?

[dddDuster]

Ok, about a year ago my fuel gauge on my 70 Duster, standard dash just settled in at about 1/16 of a tank just off empty.
Since then I have confirmed gauge works (wire to ground trick), confirmed the ground strap was in place and added another ground for good measure. I’ve added a panel ground to the dash, replaced the IVR with the RTE unit, and replaced all the cheesy nuts on the panel. I’ve checked the wire connections and their pins, I’ve chased the wire all the way to the panel and checked all connections.
Now, here is the odd part, when the gauge shows 1/16 tank the sending unit measures 65 ohms always. But, after driving for about an hour the gauge will spring to life and seem to be accurate. If full it will measure around 12 ohms, if at the 200 mile mark it will measure around 80. All is well, I can shut the car off spend a few minutes fueling up or whatever and the gauge will respond and seem to work just fine. However overnight it goes back to 65 ohms and there it sits until I’ve run it for an hour or so on a nice warm day.
I am about to decide that the sending unit is faulty and send it to be rebuilt, but want y’all’s thoughts first!

 

[Demonracer]

Look up John Wolf & Company, I think they are in Ohio. I've had 3 sending units rebuilt by them with excellent results. Whatever you do, DO NOT buy one of the chinese replacement units.

 

[Lord Sparky]

MeterMatch. Set and forget.

 

[Dana67Dart]

Meter match only would work on a fully functional sender

 

[Dana67Dart]

Look up John Wolf & Company, I think they are in Ohio. I've had 3 sending units rebuilt by them with excellent results

Any chance you have photos of the repaired sender, also what did it cost?

 

[67Dart273]

Here are the "pretty much correct" resistances all gauges should see, whether oil, temp, or fuel

 

[Demonracer]

I don't have any pictures of the rebuilt senders because they are in running cars now. I'll look through my receipts & get a price as to what it cost me.