Is your temperature gauge numerically graduated? I thought that the gauge was marked with ‘normal’ and ‘hot.’ And like most gauges they are accurate enough to indicate changes in engine temperature but not accurate enough to determine the actual temperature. If the cooling system is properly filled with clean coolant, the thermostat is operating properly and the system is in good condition it should run at 190* +/-. But as I mentioned earlier the early models seemed to have problems when idling. I have added an additional fan to the condenser and saw an improvement on Cherokees used on RFD mail routes. And, I owned several that my wife and kids drove and all indicated a problem at idle. If shifted to neutral and the idle raised to about 1500 RPM the temperature would quickly drop to normal on those with a belt driven fan. You might carefully open the hood and squeeze the upper radiator hose to check the pressure and temperature when the gauge indicates HOT. If it is above 210* the hose should be quite stiff and too hot to handle bare handed. But please be careful. I had a radiator cap blow off just as I opened the hood of an overheating truck.