jack the car up and remove the wheels. were the shock is stuck to the back beam, un-do the 13mm bolt(i think its 13mm, its in the bottom ov the shock)on both side's and now the shock will be lose,
open the boot and remove the rubber cover and un-do the bolt there, it all should come lose then. and remove,
watch out for the spring to move slighly, if it does just put it back between the 2 metal points sticking out.