Thermostat housing is above the exhaust plate on the port side. I do not think this model has a poppet valve. I searched a few different forums and one specifically said "this model does not have a poppet valve."
When I am at full throttle I have a strong stream of water from the tell-tale. I do not think it is stopped up at all.
New impeller installed and used the rebuild kit so it came with new everything save for the housing (new gaskets, plate, impeller housing, etc.). I do not think it is pump/impeller related as it did this overheat business before I changed the water pump components a little while back.
Makes me think I am running too lean with the oil again. It has the auto mix/inject system still. I visually inspected it and saw no issues apparent. I am going to run it tomorrow and see what shakes out.
Every now and again I just need to run the bejeezus out of it on the river or something and it behaves. Like you got to blow the cobwebs out of it at times.