Get the car jacked up and on axle stands at the back. Use the rear chassis jacking points.
Gently put trolley jack under spring cup on bottom arm take up a little spring pressure.
Remove bottom bolt holding rear shocker.
Remove Anti-roll bar link.
Lower jack really gently, so spring doesn't fly off.
The bottom arm should now come down enough to relieve all pressure on spring and spring should more or less drop out.

If the bottom arm doesn't come down enough to let the spring out, then take bottom arm off by removing the bolt near the centre of the car. (Take note of the position of oval washer though for re-assembly. This affects rear tracking)

Refitting is reversal of removal really, just jack up under spring cup until you can reattach shocker and ARB link.



I hope this helps.