I've tried many different TBs... car was progressively built for SCCa pylon AX... I settled with the largest size of 1.24" (hex opening is 1.25")... these TBs rated at 425 # per inch (from a past Mopar compony called California Moparts/Suspension i the 80s... they later went out-of-business... too bad, ahead of their times.
I've offered mu opinions from past experience - don't be afraid of larger TBs. Even at my current 1.24", they're not as stiff as you may think. sure, the ride is stiffer, but its completely still driveable for the street/hwy... as long as you don't routinely drive over pot holes and rough train track crossings (just slow down then or avoid that drive as much as possible... no fun!).
As HP2 has similarly said, with soft TBs your car has more of a tendency to bottom out, and the lift/lean will prevail.
Consider nothing less that ~1.12 for a SB car... or even 1.18 for a BB car... you won't regret it and only wonder WHY you didn't install these larger TBs earlier. Call Firm Feel as they readily have the 1.12 and 1.18 in-stock... and they'll gladly make you larger (up to 1.24).
ALSO, consider spending good $$ on good shocks... you pay for what you get. I recommend double adjustables (Viking, QA1, Starnge, others)... the Vikings are probably the best buy as they originated from the QA1 designs (same past people), and Viking ONLY makes 2x shocks to keep their costs down.
AND... consider stiffening your rear leafs a little... too stiff an you'll really feel it... current "handling" leafs (from various vendors) are all pretty good.
I suggest to use the sway bar sizes as a fine-tuner in the handling... your choices prevail.