Essentially you'll need to pull the struts off of your car, and then remove the coil springs.
It may be possible to do it with the strut still attached to the car, but I have no experience with this. Do you have to cut off the original spring perch?
If you're using a spring compressor, remember, everything you're dealing with is under a lot of load, and if you're not safe and careful there is a lot of stored energy in the springs.
I think John is suggesting going to get a service manual so you can do it the correct way.
You can download a few Z manuals here http://carfiche.com/manuals023/cars/ ,but you have to be able to catch it at the right time, as they cycle the manuals to save bandwidth.
Also, you could try contacting the original poster of this thread, if he's still around.
http://forums.hybridz.org/showthread.php?t=112338