Keep weight in mind going turbo, car could easily become a pig. 4l80e, iron block, steel roll bar, turbo stuff will add up quick. If I had to pick I would do:
built 4l60e
Decent cam
budget heads
Nitrous (100-150 shot)
Shocks
Toque arm
Drive shaft
12 bolt
15" wheels
Chromolly rollbar
racetronix fuel pump and hotwire kit
Weight reduction:
-Loose AC
-Come up with an exhaust with no cat back, retains a muffler to keep quiet on the street and use cutouts at the track.
-15" wheels will reduce weight