Chevy's get you about 3-4" so your going to need blocks or add a leafs to get the rear up more.
Check this out though:
http://www.offroaddesign.com/catalog/Zero%20Rates.htm
Then read this to answer ALL of your question:
http://www.pirate4x4.com/forum/showt...threadid=20665
My springs are from a 90ish 2wd 1500, 4 leaf pack.