I finally got some new bushes for the rear of my car and set about fitting them to the spare lower rear arms I had for just this porpoise. I replaced only the pillowball type bushes (31Av & 31AW in the diagram) which go in the rear inner and outer registers on the arms. The inner front (31AU) is a solid rubber bush which seemed to be perfectly serviceable on both arms. Diagram: The first job was to make a tool to push the bushes in and out with. This is a piece of 1 3/4"