I've seen a bunch of stock Mopar water temp. gauges read wrong, same thing on Autometer mechanical race gauges
Some will read high and some will read low, check yours with known good heating and air conditioning pocket dial gauge or a good hand held Infra red temperature gun before making any other decisions on this
One of my old race car had one of the expensive Auto Meter large face 320 degree reading race mechanical water temp gauges in it that would read 140 F when the water circulating in the radiator was cool enough for me to stick a finger in it and not fell any warmth
I can not let 140F water touch me without getting away from it 120F is hot to me, not warm