Caltracs ?'s

Ok I need to get going on ordering me a suspension so I can get to work on getting an 8 3/4 under my car. I am confused by what I actually need.

http://store.yahoo.com/chucker54/catrbarsy1.html

I was told that caltracs are like $600.

Also how does the Slide-A-link from Competition Engineering stack up against Caltracks? I was looking at them in the new Summit and kinda liked them and the price!

What springs should I be running with this kind of a setup?