Originally Posted by Hotrod Lincoln
Tee fittings will give a false (low) reading, since the sensor will be out of the flow of coolant and the extension of the fitting will act like an insulator. The driver's side rear area of the head beside the valve cover flange should have enough thickness to drill and tap for a 3/8" NPT thread. Use pipe dope or brush-on gasket sealer on the sensor threads.
Jerry

Thanks!

Pat
1940’s tech was great in the 40’s