Upgrading a Fairly Stock Suspension

Thanks for all the input guys! It seems most people are saying to rebuild the suspension and increase the spring rate. Can someone help me pick a rebuild kit from PST? There's quite a few on here and I hardly know what I'm looking at and what's the difference. I'm currently running Kelsey-Hayes up front. And along the lines of Torsion Bars I was thinking of going with at least a 1" bar (not initially, but we'll see). And a FF Stage 3 Box is definitely on the list of priorities (maybe early Springish). The panhard bar and watts link are new to me (I vaguely remember hearing about them once) but I'll do my research on them. I doubt I'd ever do that because as of now I'm running a 7 1/4 rear end. Would like to go with the 8 1/4 or even the 8 3/4 when I collect parts for bbp.