Great write up. I don't see the dowel in your pictures, though. IIRC, which is doubtful since it was 7-8 years ago, there was a dowel in the center of the cover that needed to be removed in order to seat the cover without rolling the rubber seal. That would cause a big oil leak and require a redo.
Short of pulling out my W124 CD, I'd have to ask if the engine versions are the same.

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Prost!