Some guesses...

Picture #2 - looks like the manual open/close mechanism for the sunroof. You put a spark plug wrench (it's in your toolkit) on the red thing and turn to open or close the roof. I think the two german words are for 'open' and 'close'.

Picture #3 - yes, it's a little low in the back. Have you changed your rear subframe mounts? My '86 300SDL had 250,000km (150,000miles) and it looked just like yours in the back. When I changed them, it raised back up. Make sure you change the differential mount at the same time -- that made a big difference in mine also.

Neal

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