190d 2.5 automatics used 3.07s, 190d 2.5 turbo automatics had 2.65s. All the gas cars were shorter than that I believe.
I think if you swap the back covers you can use 124 diffs in a 201 but someone who knows better than I will confirm or deny.
You car is a W201 190E, that may help in your online searches to use the correct terminology.
Edit, here is a link
http://www.baureihe201.de/W201/technik.htm
Note that several of the cars referenced on that chart were not available in the US.