If it was an easy convert I'd let you have my 5spd in exchange for your auto. My car is just sitting here collecting dust because I hate 4cyls and I hate sticks. Or I could sell you my whole car for 1K. I'll probably sell it soon either way since I never drive it.
Btw, '85 190E, odo stopped ~185, it's got maybe 200K, no cats, burns oil and is hard on plugs. Paint is bad, body is very good, interior is very good, seats look like new. Drives like new, runs strong, or at least a strong as a stock '85 2.3 can run.