IMO, rear control arms are fairly good to go with any vendor.
Savitske Classic & Custom good company, lots of suspension parts
If you go with the HR sway bar you will not need bags. As mentioned earlier no front sway bar with the HR rear bar.
KYB, Bilstiens, QA1s, all good shocks and lots of opinions there. Depends on $ with some options.
Stock springs usually are ok, also depends on how you want your ride hieght.
as for the rest, check out some of the threads by jdpolzin concerning springs/lowering springs, lowering spindles, ball joints, control arms (front), ect.
Lots of guys leave the front alone for racing. If you plan on lowering the car it opens a whole nother can of worms.
Doesn't take a whole lot of mods to get a g-body to hook and go. With some rear suspension upgrades, good tires, and decent shocks you should be good easily down in the tens.
I'm sure there will be others who chime in with their combos and ideas.
HTH