I changed mine a couple weeks ago, very easy job!
- Slaken the hub castle nuts on the ground (30mm).
- Jack both sides up on axle stands, wheels off.
- Remove the castle nut, and both bottom strut bolts (21mm).
- Remove the driveshaft you might need to use a mallet or punch to help knock it out the hub.
- Pull the driveshaft to one side and knock off the old ring, if it's cracked it should come off quite easy.
- Clean up the drive shaft using a steel wire attachment or rub it down by hand to remove any debris.
- Put a thin layer of grease inside the new ring and on the shaft to help it on, slowly tap it on evenly try not to damage the ring.
- Refit in reverse order, make sure to re-torque everything (Castle nut 280nm, strut bolts 180nm)
I changed both rings whilst I was at it, for the sake of a couple pound it's worth doing especially if you have camber bolts etc as the cost of having to get it realigned in the future out weighs it.
Hope that helps.