I'll bet you had a defective thermostat which did not allow enough coolant flow once operating temperature was reached.
Changing to a 160 degree thermostat would have ZERO effect on the final, fully warmed up engine temperature, (unless it is replacing a faulty thermostat).

1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission