It seems Midpiner is saying he has a 3/8 pipe thread in the head and a 1/2 pipe threaded sender. The link shows a reducer, he needs the opposite. Find another hole somewhere that is xx ....or a xx (sender thread) to 3/8 MNPT reducer. This one is 5/8-18 straight internal threads to 3/8 MNPT I don't know what size your sender threads are. Measure them. The TS6 is 1/2 NPT. You may need This
The problem will be if the probe will fit down deep into adapter so as to "sense".

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