trust us on the 2.5" wide spring will work .
and the general rule is sbc and no real extra weight = reg spring .
and if bbc or winch bumper or plow = hd spring .
good bit of info is remove the last leaf on a hd pack and bam you have a non hd pack .
good info here also . and good vendor .
http://www.offroaddesign.com/catalog.htm
as much as I have purchased over the years from them I should have stock in the company .