Timing needs to be reduced. With the stock intake manifold you can either go dry, after the MAF, or if you want to go wet you need to go direct port and run the foggers AFTER the variable intake geometry valve.
Also run 2 heat ranges colder plugs. 75 shot dry is safe, I wouldn't push much past a 125 shot direct port.
Do it right, get yourself a bottle heater, window switch, fuel pressure safety switch, WOT switch, etc..
If you are tuned don't do it because timing is advanced quite a good bit. I'm not aware of anybody that does a Nitrous specific flash, but call and ask the top ones (UM, C2, Uni..)