After doing some front end work such as New Ball Joints, Shocks and upper control arms, I had the car aligned and now it Tracks Dead Straight.
However my steering wheel is 20 degrees off center.
I have no idea how to remove it and remount it so that its on center...Can anyone help?

83 240D Steering wheel is 20 degrees off; would like to remove;How?

When they did the alignment, they should have centered it by turning the right and left tie rods equal turns. This is standard practise when these are replaced or adjusted for toe out/toe in. I'm surprised that no one checked this before you got your car back. As far as I know, changing the steering wheel position at the splined end where it mounts is a Mercedes no-no.
I have done this, though, for an older car that I didn't bother to get aligned properly, so here's how it's done: remove cover on steering wheel, remove nut, take it off and reset in a different spline position, replace nut and cover.

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1986 560SL
2002 Toyota Camry
1993 Lexus

Uh I was the one who bent the rod on the left side..they brought it back to spec by alignment...
Tie rods were bent..by me...Thanks for your answer

I believe the "nut" is actually a 10mm allen hex. If your steering wheel has never been removed before, be prepared for a fight with that bolt. Get a helper to hold the wheel and at least an 18" breaker bar to "loosen" that thing.