I think I've narrowed my temperature gauge problem down to an improper
ground at the water pump housing.  How is ground supplied to the water
pump housing? I've found that the resistance of the sender is correct,
and the gauge is functioning correctly. When I measure resistance of the
sender relative to the engine case ground, it's much much higher than
measured relative to the water pump housing..

Is the temp II sensor ground wire connected to the housing through the
sensor's body?

Brad