The answer is: either way will work.
I got a call back from 1800-for-Mercedes and was told that the rod is threaded at both ends so simply back it all the way out, remove and put the shaft in a vice or something to get the nut off to make reassembly easier.
1985 Mercedes 500SL Euro (Gray market)
1995 BMW 520i Euro (Gray market)
1992 BMW 525it Wagon
1994 Honda Del Sol Si