4" is a lot.
If I were you I'd be thinking about trading that 230E in for an off-road vehicle rather than turning it into an off-road vehicle.
IMHO, when you get that much higher you run into all kinds of new challenges to deal with from the resulting angle differences that make it a significant undertaking. What does everyone else there do/drive?
1982 Mercedes-Benz 300CD
1982 Mercedes-Benz 240D - stick