I have not run nitrous yet, but plan to, and know those who do. From the start, it is he cheapest and easiest poweradder, as well as very effectve. Some of the basic kits arn't enough. You don't want the kind you push a button to activate. Not only does it make things more complicated but can lead to accidents and blown motors. What you want is a proper setup. You want one with:
wide open thottle switch, so it only comes on at WOT.
window switch - so it turns on and off at proper RPM's.
bottle heater - to keep bottle pressures correct.
For a 75 shot, you really don't need anything much, but like a supercharger with 6psi, your not really going to get much. If your going to spray, do at least a 100shot, and the reality is that wet shots are better. However, I would suggest a stronger fuel pump and to pull timing when your spraying, or use a MSD with a retard module.
I'm no expert, but this is what I know. Maby a nitrous guru will come in here and elaborate.