after having such great results upgrading the suspension on my wife's Duster with .990 T-Bars, SuperStock rear Springs, PST Bushings, KYB Shocks, etc...

now I want to get my 70 Coronet R/T a little firmed up in the rear, the OE springs have ALOT of sag and my tires are rubbing on small bumps w/ nobody in the rear seat and a full tank of fuel.

What kind of upgrade/replacement springs are there for B-Bodies that bolt right in?

I looked at Super Stock springs, but not necessarily wanting to make any modifications other than bolt-on if I don't have to. I'd also like to retain my rear sway bar if I can.