I did this once with a Ford 351 Windsor and a C4 trans in a '74 Bronco on 44 inch tires, good result, off the line response was better and better MPG. But there is almost a 250 horsepower gap between that and your car and some more pounds in weight. I don't think this will give you enough change to spend all that work on it and you will lose some of the more fun characteristics from the original transmission. In the year 1988 after mimicking Americans for 30+ years Mercedes was getting the hang of making automatic transmissions though that skill has somewhat faded since production began on the 722,6 transmission.

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600SEL '91
300E 4Matic '88
240D '83
280SE '77
350SE '73
The most complex systems can fail in the simplest way.
Contra verbosus noli contendere verbis, sermo datur cunctis, animi sapientia paucis.

i don't believe in the lord! He's never bought me a Mercedes Benz.