Thanks for posting. From the replacement part photo I see the groove in the post/stud. I've seen other German connectors with a U shaped wire clip with a wide (open, pulled out) position) and narrow (closed, pushed in) position. Pull clip out to release and lift connector off. Seat connector and push the clip in to lock. I don't see an outer edge of a clip to pull on the MB connector. Since you've had luck with brute force, and the post groove edges look rounded, I'll stop overthinking this one and just pull more forcefully. Thanks.