is to disconnect the tranny oil line at the cooler and discharge to a jug. You add 3 quarts, run engine at idle for ca. 45 sec (until 3 quarts are discharged), and repeat until you have pumped 12 new quarts through.
This is after draining what was in the pan first.

I'm not sure how the MB cooloer connection is, but the physics of the Dearborn trick should work just as well on Stuttgarter Eisen.