Blaze -- depending how far you want to go with the upgrades, I'd look at an entire new package. What's your intentions with the car? Here's some simple quick thoughts (assuming basic fun driving):
Front Sway bar... 1.25" (hollow)
Rear sway bar... stock is .75"... but I suggest a custom bar made at 1.0" (Firm Feel can make it); otherwise, the Hotchkis or Helwig rear bar under the axle is adjustable... set it a full stiff... I think Helwig's bar is 7/8" (better than Hothckis) I have a customer factory-style 1" bar and it balances the front 1.25" bar very well.
Torsion bars... assuming you have a small block, with or without A/C, I suggest at least 1.12~-1.15... as soon as you install anything larger than stock (~.89), you'll notice the difference... BUT then you'll say that you should've gone stiffer. So, at least 1.12-1.15... the 1.18 from Firm Feel or their 1.20-1.22-1.24 will be everlasting with satisfaction (they'll make you 1.24.... I have 1.24 and love them!).
Rear leafs... Firm Feel, Hothckis, others... typically rated ~160#/inch.... but you want to make certain that they are NOT high arch... you want them settled and relatively flay for best handling (and compromising for some load that you'd carry).
Shocks... spend the money and don't be cheap... today's double-adjustables are great and well worth the cost. IF not, then go with Bilsteins (the Hotchkis FOX are not bad).
Consider better seats... with good side bolster, and a smaller steering wheel -- assuming you have power steering, be certain you have the Saginaw pump... the Federal pump is not good at keeping up with rapid motion... and... eventually get your PS gear boix rebuilt to a level-3 firmness (Firm Feel or Steer & Gear can do it the same way. Everyone I know who had their ps box rebuilt less than the level-3 wishes they had gone with the level-3... I have level-3 and its excellent (further being a T/A box).
IF you want fast ratio power steering, be certain that you use the Fast Ratio Pitman arm, as well as the C-Body (~1970) longer idler arm... also called/referred to as the "fast ratio idler arm" which corrects the steering geometry left-right. IF you have headers, some brands clear a-ok (Hooker 5115, Hedman) other are questionable.
For your rims/tires, remember that shorter sidewalls increase road harshness, but are quicker for rapid steering response (autocross, etc.). You may want to eventually have at least two sets of rims/tires for your intentions... 60-series cruising; 50-45-40-35 series for autocross.
Also, consider changing your upper control arms... so many different suppliers... purpose is to get positive caster and some negative camber (keep toe at around zero)... adjustable (Hotchkis, SPC, Magnum Force), UCAs are preferred ... fixed UCAs would further benefit from the MOOG offset UCA bushings (installed reverse from their directions).
You may spend 1-2 years easily getting the car completed, as well as some increasing costs. All depends on how much you want to enjoy the car.
Good luck and MoPower to ya!