Remove the 10mm nut from the top of the shock. Pictured from above.

Hold the shock body with your hand while removing the nut to prevent the body of the shock from turning as you turn the nut.

Once this nut is removed the shock can be removed from the car by tilting the top away from the engine, out of the slot in the bracket that bolts to the engine, and then by pulling it up out of the hole in the mount on the cross-member.