A couple of points:
1. Do you drive with your headlights on? If so, with the headlights off see if the temp gage drops running it a bit more. If the temperature drops some, the problem may be the Instrument Cluster Voltage Regulator. They do go bad and when they do, the temp gage reads false hot as the unit (attached to the back side of the instrument cluster) does not balance voltage and current properly. It's not a big thing...check out the ELECTRICAL section of the factory shop manual (1951 edition) for more info on this. I had this kind of problem on both the Business Coupe and the second 1952 4-door deluxe I had.
2. When was the last time the thermostat was replaced or do you have one at all? Over time, they to corrode and otherwise wear out and tend to stick closed blocking water flow. These days, since you don't usually drive the cars in the winter, a thermostat may not be needed in most parts of the country.