Definitely got a 180 t-stat and tested it before installation on the stove in a pot of water with a gauge in the water and it opens right at 180.
My coolant gauge goes right up to 80 in the first 2 miles or so but once t-stat opens it cools back down to 70 and stays there.
Oil temp runs hotter when playing on the street but not open road cruising.
I'm going to stick with the 180 t-stat.
I just cut 3 different pieces of Lucite and will experiment on my next trip. (4", 6" & 8")
No more running at 70 in cool country for me.