Temp gauge not working Chevy C15

[TCLARK]

I am now trying to get the temp gauge working. The sender seems ok
it tested 900 ohms cold and about 200 ohms at engine operating temp.

I am not sure if I have the power on the proper side of the gauge, in
the pic I am pointing to the terminal that would go the sender.
When I shorted that sender wire out the needle should deflect to hot.
It does not. im wondering if I should put the power on the left terminal and the sender on the right??

I can abandon this and order a new bolt in gauge thats non electrical
but fun to tinker with this. I know the gauge worked on the bench before
I installed the cluster . All grounds are good ,I even took the gauge off
and tested the fine wire inside and it was grounded,also there is 6.7 volts
going to the gauge, the fuel gauge works perfectly.
Cheers
Terry .