Water pump temperature bulb sealant

[Model51]

Is there any sealant needed for the threads of the nut that holds the temperature sensor in the water pump? The nut seems like straight threads and not pipe threads and there's a lip on the top of the sensor that the nut appears to press against. I'm assuming the sensor and nut don't require any sealant, but I'd rather do it right the first time. The engine is for a stock 1935 Ford and I've attached an image of the sensor and nut only part way installed in the water pump.