Lots of posts on this subject in the SUspension forum. Here's one
http://67-72chevytrucks.com/vboard/s...l+joint&page=2
FWIW, I did it on a burb in a pick-n-pay yard with a bottle jack. Once the pressure was released I actually had to push the LCA down with my foot in order to pull the spring out. I also put a chain on the spring and around the crossmember just to be safe. I wouldn't hesitate to do it again.