Is the car not hooking now? With the BB I'd leave the SB T bars in it, /6 bars may have to be cranked way up to raise the front where it needs to be. Good S/S springs, LONG shocks, and a properly set up rear spring hanger that lets the chassis rise are needed. A 2" shim between the top rear shackle bracket and the frame works wonders to let the shackle swing forward as the chassis rises. Long shocks or shocks with extenders will insure you're not using all the shock travel up and topping out the shocks. The pinion angle needs to be checked too, and either wedge shims or welding on new perches at the right orientation for the proper pinion angle.