You can't change the Drive Shaft Support and bearing without loosening the nut and you need to collapse the drive shaft to remove the inner rear control arm bolt on aW123. I don't think you can change the flex discs without collapsing the shaft either.

In post #3 there is a picture of one of the drive shaft alignment pins and the shaft has to be collapsed enough to clear the pin in order to remover and install new flex discs.
w123 Flex Disc Recommendations??

In post #4 is picture where I needed to remove the right side inner control arm bolt to change the bushings on the control arm.

I tried loosening the flex disc and prying it out of the way with no luck. I also worried the prying was going to damage a 2 year old flex disc.
If it is an an old flex dic they are going to be too stiff to pry out of the way.
sub frame replacement?

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84 300D, 82 Volvo 244Gl Diesel