How Shall I Suspend My Rearend?

Hey gang,

I'm at a crossroads in deciding which rear suspension set up best suites my needs.

What I have:
1970 Duster with a 410 Stroker (all forged internals) making 500hp/550 ftlb.
Planning to run a 150 shot of Nitrous down the road.

Built TorqFlite 727

Dana 60 w/ 3.73 gears. Axle housing = stock length

Super Stock Springs with Cheapo Monroe Shocks

The car is almost ready for paint. I'm trying to figure out what will work best and is most cost effective for a car that will be 80% street and 20% track before I bolt'r back together. I don't really want a pro-touring set up. I want it to have that old muscle car feel and also hook up when accelorating hard.

Tips and suggestions welcome. I'm no suspension expert so any insight is appreciated.