I should mention that I replaced that stuff to eliminate the added heater from the previous owner and for PM. It is an early model (1989) 770, and I wanted to make sure the cooling system was well maintained.
The previous owner installed a heater into a homemade cab (Extremely Thrifty) and temps would never even register on the gauge. The heater, which was fed from the tapped radiator hoses, was about 1/2 the size of the radiator and would barely get warm to the touch. I felt that this was bad to run the tractor so cold ( would consistently smoke at idle) so I removed the heater and everything else besides the canopy. Once the cooling system was returned to stock with new parts, the tractor began running better and quit smoking.