Sorry to have skimmed your post and got focused on the SL part!

There is some information in the FSM (available via MB startekinfo)...

http://www.startekinfo.com/StarTek/outside/12264/Program/engine_605_comb.htm

...that might help (if you don't already have the FSM => though this is for an OM606 that is fitted to a W124 - W210 stuff isn't released for free yet)

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!