Which rear end with posi and BIG power??

[pano911]

69 Malibu with 509 all aluminum Twin turbo.....1100hp, 1100ft/lbs. Street car/ G-machine. Biggest posi combo in a 9" True Trac is with 31-spline axles....will be on street tires most of the time but on occasional will pump up the boost with race gas (1800hp) and go to the track with slicks....afraid I might break a 31-spline axle.

I could go 35-spline in a 9" with a Detroit Locker but I'm afraid of that on the street/in the twisties.

What about a Dana 60 with a True Trac/ 35 spline? Too bulky/heavy? Other options???

Definitely need a posi for the street....no spool...gonna have serious power and lots of weight (I'm guessing 3600-3800lbs)but I'm leery of a Detroit locker on the street... Help!!!!