Electrical questions

[Chevy nutcase]

I recently noticed the temp gauge on my 66 c10 never even wiggles so I'm wondering if its the gauge itself or the sensor out on the water neck and how I can go about testing the two components?

My other inquiry is concerning my recent upgrade to front disk brakes. The proportioning valve has a sensor and wired plug included which I'm guessing is for a warning light. Do these trucks have a dash light for when the ebrake is pulled and could I connect the sensor on the proportioning valve to it so I could be made aware of a problem?.