Had to think for a second…
I don’t know if this motor is an odd design, but the thermostat is where the water returns from the radiator, it is attached to the suction tube (as I think the technical term is…). Rather than let water into the radiator it opens so it can suck water out of the radiator. I had to run this through my mind a couple times…I don’t understand why if you take the cap off and rev the motor it doesn’t blow coolant all over. Maybe because you keep the same volume in the motor all the time and it doesn’t have any left over to blow???
My Haynes manual only has a diagram for Nissan’s 4 cyl. But I am fairly sure I am correct.