Remove wheel, remove the clamp bolt on the ball joint, use a ball joint removal tool, to take the ball joint pin, from inside the clamp. Undo the other two mounting bolts for the lower suspension arm. Now with the suspension arm removed from the vehicle, drill out the three big rivets which hold the ball joint to the suspension arm, fit a new ball joint, which is mounted on with three bolts to replace the three rivets.
In the absence of a suitable pedestal drill, it may be possible to use an angle grinder to remove the rivets, but you might damage the suspension arm, you might also be able to use a grinder with the arm still on the car.
In the absence of a suitable pedestal drill, it may be possible to use an angle grinder to remove the rivets, but you might damage the suspension arm, you might also be able to use a grinder with the arm still on the car.