To time the flywheel to the engine simply mount the timing windows to the same position as the outgoing flexplate.

There are different length manual and auto speedo cables but the automatic one is longer so you can reuse it.

You will need a manual W201 cross member because the manual transmission is shorter. I think I still have the only that came out of my 92 190e 2.6 5spd before putting the transmission in the 300d. Let me know if you need it.

The mount is the same. You will want to use a new one tho.

Quirks: Install a new slave cyl before putting the trans in the car. The W201 trans tunnel is very tight and its virtually impossible to do the job with the trans in the car. Also its very difficult to bleed the clutch by pumping the pedal and opening and closing the bleed valve. I used a mityvac.

The 3 shift rods are about 3/4" shorter on the W201 than the W124. You will need to modify or get new ones

The pipe between the master and slave cyl are different between the W201 and W124. You will need to get a new one or try to bend the existing one.

The 260e and 190e have exactly the same manual front driveshaft length so just reuse that. I'm using the 190e 2.6 manual front DS half in my W124 300d.

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CENSORED due to not family friendly words