292 engine temp sending unit

[Belair51]

I have a 1967 GMC with a 292 engine. Cannot find the temp sending unit. There is a wire going to the front of the engine that is not hooked up. I read that the temp sending unit on the 292 was located in the lower part of the thermostat housing, however, there is a nipple located there with one of the heater hoses connected to it. Can someone provide information or diagram as to how the heater hoses and the temp sending unit are set up on the 292 engines? Would appreciate any help or comments.