1990 sentra thermostate not in normal spot no houshing missing????

[Tempist]

been turning wrenches for a long time and this one is new to me. normal thermostate housing is in the right side of the head with therm sensor. and there is nothing there. i'm not kidding. there is a metel tube going around the back of the head going all the way almost to the other side. can't see the housing there as well. stuned!!!! also this site has no manual for this car. my mother-in-law said its a special edition??? if anyone has a clue pleasr help me out.

[Hijacker]

The lower radiator hose attaches to the thermostat housing. If you're not having luck identifying the housing based on previous knowledge of other cars, trace the lower rad hose back up till it reaches the housing.