I agree 110% with UNGN. I don't have any experience with sway bars on G-bodies other than on our current car. It originally had a tiny front with no rear - with this it drove like Mom's grocery getter when cornering - tons of lean and not responsive. We found a stock front from an SS Monte Carlo that was much larger - this helped the body roll a bunch. Then we put on a UMI rear sway bar and it was night and day. I wouldn't recommend the UMI rear bar without aftermarket LCA's due to the stiffness of the bar seems like it will rip up the stock LCA's/
Good luck - Jim
Good luck - Jim