My 2003 has the marks only gauge. When I try to search online to see what numbers the marks denote I just
see results of temp sending unit stuff instead.

Today I was able to run it to bleed the air from the system. The needle went to just shy being plumb vertical.
I was back and forth watching the gauge and observing the air bleed from the bleed port. I placed a 2" 3/8 nipple
in the port to be able to see bubbles escape but not have coolant running over. The coolant level was staying higher
than the level of the port hole where the plug goes.

When I was first refilling I would spin the water pump by hand, had yet to install the fan. I wasnt sure if that would move coolant around
inside hopefully to decrease air pocket volume. With it now running and warming up Im watching the bleed port with the expectation of
seeing the level drop when the stat opens. After a while running with the temp needle staying just under a plumb stance I shut it off.
I dont like reaching down with a steel fan whirling around! With the fan stopped I feel of the lower hose and its not warm at all. I even
grip the neck of the stat housing to have that not feel warm yet reaching back to what the stat housing bolts to is very warm. The heater hoses
were very warm. I wonder now if I got a dang dud stat thats not opening?

Maybe it was just on the verge of opening but I didnt want to push my luck. Having numbers on the temp gauge would be a handy feature.................

 

So long as the needle stays out of the red, should be ok. I expect them to get pretty hot just before the stat opens the first time....