Originally Posted by Ivanerrol

The flange that connects the tranny to the flex disk must be changed.
The speedo drive is different between 722.3 and 722.4. You will need to get a speedo from a W124 260e. (260e's are equipped with the 722.4)

The 722.4 is meant for light weight use. It's capacity for handling torque is much reduced compared to a 722.3

I would not put a 722.4 from a W201 into a W124