You definitely have majority of the basics already installed on your Sixxer. The only real improvements you could do to make more power would be, Long Tubes, O/R X-Pipe, 3.73 or 4.10 Gears, Throttle body or some sort of power adder! The new V6 handles nitrous pretty well, a 100 shot would be awesome with your current set up.
Keep up the great work with your build and hit me up if you have any questions or need some assistance in the near future!
In interested in a nitrous set up! I see you work at american muscle where I buy everything. There is no nitrous kit on your site. I would be interested in a kit and a Bama tune to go with it . maybe a hybrid tune so I wouldn't have to change tunes just to play with the nitrous. Any suggestions?