The 4-71 is a LOT bigger in every dimension than a 4-53! Shoehorning one into a 19xx can probably be done, but it would be a fabricating nightmare.
As J.Schwiebert points out a 6V-53 will be a better choice. It won't be a "drop in" replacement for the 4-53. But it would be much easier to adapt the flywheel, clutch housing, radiator, etc.
There were a couple 6V-53 repowers running around here for a while. One was a 1950; the other a IH 806(?). Both were working tractors. The IH also did well (and drew a lot of attention) in the "field class" tractor pulls for several years.