Why does it have to be a wet system?
I talked to a guy that builds race cars and he said that you just drill a hole into the side of the intake and have it spray into the intake directly.
Because "dry" means there is no fuel enrichment, just shooting nitrous with no extra fuel will lean out your motor, plus, that nifty plastic Intake
manifold on your motor will shatter into a million pieces when your motor coughs with a 50 shot of dry N2O.
You can only go dry if you add new programming to the ECU to enrich the fuel, and driving without nitrous will make the car run rich.
If you go with a ZEX wet system, you can do the whole "tap the Intake
and install a fogger nozzle" thing, it suppliments fuel and nitrous through the same nozzle, and it's a lot safer than a straight dry setup. Multi-port nitrous is a lot safer still, as each cylinder gets equal amounts of N2O and fuel.
If you go the ZEX route, be sure to install your nozzle after
the MAF sensor, or in other words, in between the MAF and the throttle body. putting it before the sensor will mess the sensor up, or possibly cause an explosion (MAF sensors are a glowing-hot wire of platinum!) fuel + N2O + glowing-hot filament = BIG bada BOOM!
start with a mild jetting (35) for street driving, only run 50-shot jets at the races, otherwise you may wear out engine vitals a lot faster.