F-150 radiators

You can swap the rad out if you want, but I'd suggest a removal and cleaning first, and then I'd use some kind of electronic means to actually see the engine temp (like the torque app and a bluetooth OBD2 connector). Ford's gauges are notorious for being idiot lights with needles and all but useless.

But hey, If you would prefer to just add a new radiator and swap out the coolant - go for it. I'd add a serpentine belt, thermostat, and upper and lower rad hoses to that list though.