I have a cool and easy way to do it.....Just did it the other day...had to replace some idlers in a ZL500
1. Park your butt on your sled..... unless you can find a bigger one, thats good too!!!
2. Find someone to help you, and have them hook two vise-grips (one on each spring shaft) where the torsion spring's shaft goes through the mounting hole down by the front arm mount.
3. Get off of sled
4. Suspension will stay in that compressed position..... shouldn't need to loosen idler wheels, or track. Might have to just a little, but the fun is when it goes back in, no hassles..... since the springs are compressed, you can move the rear arm much easier....plus it is more compact..... easier to move around.....
I pulled the skid out the old way, but a buddy of mine helped me put it back in and thats how he did it, I was impressed, not having to unbolt the springs at all!!!
Just my $.02
Steve