Yes, it is definitely a resistor. I removed it for the photo and then connected the wires directly as a test. When the resistor was bypassed the reading on the temperature gauge increased significantly. This is a late 1974 car and the resistor was likely installed at the factory to help match the sending unit to the gauge. On a 1971 car that I had they actually soldered a bare resistor into the circuit making this white unit look sophisticated.
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