No, but thanks for the proper terminoloigy. I guess the bottom portion, which you show, is the :"thermostat housing." The truck did not come with a radiator (another story) so that hole is plugged and evenutually will have the heater outlet.
The PO mounted the probe in the upper housing (water outlet) - the piece that has the water outlet to the top of the radiator. I don't think that's the correct housing for the 216. In fact I know it is not, because it has 1 1/4 hose, where I think 1 1/8 is correct. I am using 1 1/4 shimmed at the top end.
SO, the thinking seems to be that it should go in the hole on top of the head, where I removed the 5/8 x 11 threaded plug. But how?
Thanks again, and I will see about posting in the engine forum.
Harry