The easy way is to undo the bottom nut on the old shocker, then the four turret retaining nuts. Be very careful with these as they have a tendency to snap easily!! :?
Then you can pull the turret & shocker out in one go from inside the engine bay.
Remove the top shocker fixing and put the new one in. :D
Having said that, if you snap any of the turret retaining nuts, then the spring has to come out to replace the retaining ring which sits on top of the spring. :(