The OM606 seems to be well suited to your power goals. 

There is no problem in making the 606 work in an allien body if you swap in a mechanical pump. 
If there is no brain to think then there is no brain to believe 
Once you do that it is only a matter of making the motor fit.

If you want a manual transmission you could use one from a 190E or a 190D. It will bolt on to the 606.
If you want an automatic you could use the stock 722.6 that comes with the 606 with a standalone controller or an older full mechanical 722.3 from a 300D or 300SDL.

There has been some talk about a jeep 27 spline output flange that will fit on Benz transmissions and allow you to use a drive shaft with U joints.