[VetteVet]

I'm afraid that I couldn't recommend this workaround. The resistor is a fixed value and the sending unit resistor is a graduated curve. What that means is that the resistor is linear and the sending unit is variable. This means that the gauge will read cooler across the band and might give a cooler reading than what is actually the value.
Having the correct sender and gauge resistor is the best way to go IMO.

Comparing the reading with a known good gauge and sender and the resistor on the gauge itself would give a better indication of the correct value for the gauge resistor.