Yes I did burp out all the air and it is filled with no leaking.
What's the best way to measure the temp?
as far as measuring resistance that's not something i have ever done but willing too try- not sure what it supposed to be but will dig around.
newly installed Thermostat is rated for 195° (at least that's what was stamped on the flange), brand new. how do i tell if it's not working correctly?

 

Again, jjrbus gave you the suggestion a few days ago. Use an IR temp gun. Point it at your thermostat housing.

it's all over the internet. Search for "how to test an engine coolant temperature sensor"

Again, web search is very powerful tool. "how to test an engine thermostat" gets a lot of excellent video hits.
thermostats responds to heat by opening the valve, so ... heat it up. Drop it in boiling water, hit it with a torch, or heat gun ... use your imagination.

When doing any kind of electrical troubleshooting, I always have a schematic on hand. Do you have a Haynes manual or something? If not, try searching the web.

By process of elimination you should arrive at the culprit. My money is on a faulty gauge.

 

me too - thanks for all this. will have at it.

 

used a IR gun and got a reading of 190° off the thermostat housing while it was idling. had been driven for 30 mins before i checked. was fairly cool out today too. I think i'm gonna call it a lazy gauge and get back to replacing the clutch in my mini cooper. huge thanks to everyone for all the input!