The CVJ is held on to the shaft by a spring clip, best way is to remove shaft from vehicle, hold shaft in vice (vice must be secure and robust) tap wedge between outer cv casing and vice, then hit other side of outer cv casing hard with a heavy hammer this will compress spring clip and allow shaft to be withdrawn from CVJ. Now you can clean CVJ out and repack with grease, slide new boot onto shaft refit CVJ to shaft. I had to work this out for myself, so I have put the answer so it may help others.
Nick Johnston, March 2008
