'62 Temp Sender for Guage (not light)

[62ShortStep]

I'm installing a '62 factory instrument panel with full gauges (not lights). It looks like it came from a larger truck since it still has an 'AIR' gauge in it.

My problem is I cant find a sending unit for the temperature gauge.

I can adapt another sending unit if I need to, but I need to know the ohm range for the original sender.

I tried to determine the ohm range by substituting the sending unit with a 500 ohm potentiometer, but I cant get the temp gauge to read past dead zero. Only when the pot is set to 0 ohms does the gauge bump a little (in the wrong direction...I hope I don't have a gauge issue too!).

Does someone know if senders are available, or what the ohm range of the sending unit is?

thanks!