From my understanding - based on my W123 experiences - once you've got the prop shaft in place you need to tighten the big nuts. I don't think they are designed to be sliding on the splines. I think any give and movement in that part of the car goes on the rubber bit of the centre bearing assembly.

As for which way round the centre bearing goes... I'm not sure I'll check...

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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!