It is a massive job as I wrote "a nice and fun job". It can be done on one side
https://www.renault4.co.uk/forum/threads/fossicking-in-the-garage.10103/post-77782
but read also the comments and other experiences
https://www.renault4.co.uk/forum/threads/rear-outrigger-bushes-and-refitting-them.11398/#post-78545
As the outer bush of the swingarm already has to be replaced, the other side as well offcourse, than best thing is to remove the complete rear axle (gastank has to come off also) to get a good look at the overall state of the rear chassis beams, rear mounting corners of the chassis, underside C-pillars of the body and many more R4 rust sensitive places as you can read here
https://renault4.weebly.com/belangrijk-bij-aankoop.html.
You could run into surpises from the R4 rust fenomenon as seen on the attached pictures. I don't say it is but it could be as it is in 99 out of 100 cases.
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