Hi Danielle, My r33 temp gauge sits just under (bee's dick) halfway at operating temp. The thermostate regulates the temp of the coolent in the system. I would remove the thermostate and test it, to be on the safe side. it sound like the thermostate has been sticking open at times before the water pump was done. My fan has a couple of cracks in it as well, thats just from age. If they are really bad replace the fan. I have worked on many nissan vehciles over the years and i've found the temp gauges on various models to site about halfway or slightly under at operating temp.
Regards
Clynton