Yes I am sure of the ohms readings. Was a standard across early Dodge products.
72-73 Dodge MH chassis would have a 5V voltage limiter (regulator) mounted inside the fuel gauge. This limiter supplies the reference voltage to the fuel and temperature gauges. Do you have a problem with both? If so then that points to the limiter as the problem.
Vintage Chrysler electrical repairs and updates (part 2)
On fuel gauge:
Light blue wire (A terminal) is the signal from the tank sender unit.
Dark blue wire (S terminal) is the 5V reference voltage from limiter to temp gauge
White wires (I terminal) is 12VDC feed from ignition switch via the 20 amp T/S; B/Warn fuse in the fuse box.
Do not forget Winnebago either used different posts off the fuel selector switch or installed a relay under the dash to select between tank inputs.