There appears to be a "cone of silence" (Get Smart tv show from the 1960's) about any Mercedes Benz parts swapping especially transmissions and such. It aint like Chevy engines and transmissions that will bolt up to almost anything. I had a brainstorm about possibly swapping an automatic transmission from a 2.3 8v engine or possibly just the torque converter to possibly get some better acceleration from a 190e 2.6., Just like the old Chevy Vega torque converter swap on cars equiped with a small block Chevy engines and turbo 350 trans.
When I find out I will be sure to let everyone know.
Sorry I could help you but I'll ask around.
1990 190E 2.6
1996 Grand Voyager 3.3
1985 Mustang GT 5.0 5 SPD
1982 Suzuki GS 750T