help me choose rear end setup

Its definately more of a street cruiser. I would love to go to the track once a month or so, but since I work a lot of nights and weekends, my time with the wife and kids is limited so Ill be lucky to see 6 track sessons a year. Plus my car is by no means set up to be a consistent bracket racer, so the track for me is just for fun and to stomp on whatever corvettes or camaros show up.