According to TractorData.com, the original engine on that tractor was a Tecumseh H80.
That Kohler K241 is a big horse of an engine compared to the Tecumseh.
The smaller Kohler K181 would be a lot easier to put into that MF tractor.
If you're determined, the K241 can be done.
I suggest you get a piece of cardboard , fold it 90 degrees, and mark the position of the Tecumseh crankshaft on the cardboard. You will need to position the Kohler engine in the frame so it is the same height from the top of the frame and the same distance from the right side of the frame.
That will minimize belt alignment issues.
You may need to cut the frame down and build a new plate to bolt the engine in, or you may need to shim the engine up higher.