Thats a good idea measuring the ohms at the guage end to compare it with the ohms at the sender.What i meant by"Then I ohm the sending unit and it is pretty much ground out as it sits. "I ohmed the sender off the tank strap bolt and then checked the ohms from that bolt to the other strap bolt and the readings were close to the same.I was useing a needle type reader set on x10 and it read about 6 on the sender and 5 on bolt to bolt.Also the tank is empty.
"I do have a electronic resistor that is installed and is suppose to shut down if too much power is going to the cluster."It was late when I posted this and I couldn't remember what they were called but its a solid state resistorwith a built in fail safe like the ones you offer.Actaully I seen yours after I bought mine.
Thanks for the temp wire color also.