pain in the backside mate! you will need to ideally take off the the bolt holding the bottom arm at the bottom of the spring...but as normal focus style, they are probably siezed on...which will mean new bushes time as you wont get them out without damaging them!
I gave up on mine and took them to a place with a ramp who put a big bar over the spring while someone put as much weight on the wheel as possible to give it extra room and wedge it out...dangerous but thats the only option we had without taking the car off the road till new bushes arrived!
bassboy