Temp gauge not moving much

[76JimmyBlue]

The temp gauge on my '76 has never really moved past cold, even after driving for long periods of time. Actually the one time it got close to middle of the gauge was when it has a leak in the radiator haha. Havin trouble testing the sender but when I ground out the wire the gauge pegs all the way hot. Which I believe means the gauge works. The other option is if the thermostat is getting stuck or pushed open. It has an original "AC" 195 degree ( if I remember right) thermostat which I tried testing in hot water and seemed to open up fine. The upper rad hose immediately pressurizes on a cold start up like the rad isn't being bypassed by a closed t-stat. Also where on the gauge should the needle point/ what's the normal operating temp once warmed up? SBC 400 engine.