I replaced a broken O/S/R spring using this method. There may be other, better ways but this worked for me...
Jack the car up so that the wheel's clear of the ground. You don't need to have it particularly high as there's little need to grovel about underneath. Jack the swinging arm a little to tension the spring (or the bits of it if it's broken). Remove the lower shock absorber bolt (21mm). Remove the bolts securing the anti-roll bar links to both swing arms (17mm) and slacken the upper link bolt so that you can move the link out of the way. Clamp the flexible brake hose between the body and the swing arm, then disconnect the fixed brake pipe (11mm) from it. The tube nut also clamps the flexi hose into a bracket. Once it's free, tap the flexi hose out of the bracket.
If the spring is broken, simply lowering the swing arm should allow it to be removed. If it's still in one piece, it will have to be compressed to get sufficient clearance to remove it. Use proper spring compressing clamps (with the bolts facing downwards) opposite each other. You will need to compress the spring by over 75mm (3") to get the clearance you need, so position the clamps to enable you to do this.
Warning! These clamps can unpredictably slip, fly off and cause damage. I used jubilee clips around the
to minimise this risk and I got away with it, but please be aware of the danger. When the clamps are on and tightened, prising or forcing the spring to remove or replace it would obviously exacerbate the risk, so make sure you've compressed it sufficiently before trying to remove or replace it.
To increase the clearance you can also remove the top bump rubber which is attached to a plate with a stud that screws into the top spring mounting. You can just about get a pair of grips between the spring's
to undo it, having liberally WD40'd the stud first! Alternatively, and if you're well off, just cut the rubber off and unscrew the plate afterwards, replacing it when you replace the spring.
Lower the swing arm sufficiently to allow the spring to clear the swing arm locating hump and manipulate it inwards (towards the diff) to drop it out. I didn't disconnect the drive shaft and there was just enough tolerance for the swing arm to be depressed without it popping out of the inner CV. But there is a danger here, so beware!
Reverse the procedure to replace the spring, making sure that you place the removed (or new) top bump rubber inside the
, just resting on top of the swing arm. Once you've jacked up the swing arm and removed the spring compressors, you can manipulate it back up and screw the stud in. Making sure it's clean, greased and screws in easily while the spring's still out of the way obviously makes this task easier.
Be careful unscrewing the bleed nipple (10mm) on the caliper. It's a steel nipple into an aluminium housing, tightened enough to hold the Titanic and will snap off very easily if not treated with respect. Use a slow steady pressure to start it off and then keep working it back and forth, each time increasing the radius of turn. 5 or 10 minutes spent doing this is worth many hours of messing around with drills, taps or replacement caliper.
I don't think there's much point in replacing the springs for the sake of it given the effort involved. My local independent factor quoted me £49 for a new one, Hylton Renault's was £25 with next-day delivery (both prices plus VAT).
In summary:- If you've a broken spring it's a fiddly job, but do-able with care and spring compressors. Best to allow 2-3 hours per side.