The sender is P/n TS -58 at Autozone, Ford, Pep Boys etc, etc. Be very careful someone tries to sell you a different number- that would likely be the sender for an idiot light, which will not work. Getting the right sender will not guarantee you correct temperatures on your gauge, though. You really need to calibrate the system in your car to verify, and you'll probably need the 'factory' 10 ohm 1/2 watt resistor in the gauge line. But to calibrate it, use a variable resistor and a glass thermometer in the swirl tank.
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