Steering wheel removal is on this site somewhere. It is easy. There are a couple screws on the forward side of the wheel (facing the cluster) that hold the airbag in. Remove those (I think they are allen head, if I recall) and the pad and airbag come out. Unplug the airbag (disconnect the battery if you are safety conscious), the wheel comes off with the big nut in the center. I replaced mine in my tech's shop, and we didn't touch the battery; he cautioned me to be careful not to f*** up the airbag electrical connector, to pull it straight off. Other than that, nothing to worry about. Center the wheel before you remove, and center when you install.
This is what I did with my 124, can't guarantee it is the same for you, but many of the newer wheels come out this way.
1985 300TD 4-speed 212K
1992 400E 343K
2001 E320 72K