Just TOO cool

This is the second new thermostat (the first new on was a 180)
I blocked the bypass after I couldn't get it to warm up all the way.(so I don't think the pressure is pushing past the thermostat, as it didn't change a thing)
It was however quite the pain to get it filled with coolant when blocked, and I expected that.
My thermal electric fan controller has marked temp settings on it, so I know the guage and actual engine temp are pretty darn close. (I can set the contoller to come on at 210 and it does come on when the gauge says 210.)
Thermostat upside down would make it overheat instead of over cool.

All the above are great thought's, but I've already been there.