FIJIBLUE72

I have a 1972 cutlass supreme convertible. The car orginally came with a 350/350 combo.
I have replaced the engine with a 455 built to W30 specs. I also replaced the transmission with a TH400.

I don't know what gears are in it, But I know it is a "one legger". I would like to replace it with a limited slip type rear end. Any help/thoughts on a good combo would be appreciated.
This is no race car, but I just want to make sure it has some good streetable power. I would also like to be able to put it on the higway without being at 5000 rpms to do 55-60 mph. The only mod to the engine was to add an HEI distributor. Stock quadrajet and intake... etc...

Thanks

gearheads78

I would use 3.42 gears as a good compromise.