May want to check with the dealer to see what they would charge. They may have a special tool that makes it quick and easy.
I had a 86 535i and did the bushings, Think I burned them out but it was a long time ago. Anyways when I was picking parts up one time the guy said that its not the expensive to have done becuase they have a special tool that pops them out in place.

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Currently driving a very clean 1985 300SD from the West Coast.