You can build one up to hold as much power as you want, an easier option might be to use the M104 converter plate on the M120 722.6 gearbox. I have no idea on the dshaft itself but for sure at that power level you'll need to be looking at changing the guibo's. You might look into Chrysler 300 and dodge charger performance. A built NAG-1 is the same as the 722.6 box and they could also point you in the right direction for d-shafts and rear ends.

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1993 190E 2.6 Sportline