Ok, now I understand, and yes I have seen it during my 1982 300TD wagon complete suspension rebuild, front and rear.
I have done a few things on W123's


I would again go with my advise as posted. Make sure the allen wrench is the correct size. Some "cheap" tools are not quite up to specs at times, I know I have lots of them. If you have access to an impact wrench it may work well for you. An impact wrench will provide the short, strong bursts that could do the job and not strip it.

Dave

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car