I cant seem to find a water temp gauge, mechanical stud type, to fit a 3/8 npt fitting.  Most of them have a capillary tube and require electrical connections.  I want a gauge that reads from 100 to 280 degrees so that the 200-220 degree is somewhat in the center of the sweep.  That is usually the accuracy area.  Any ideas, brand, etc.  I intend to install it in a "T" fitting at the heater valve area, directly in front of the carb.