dry shot is before MAF and wet (fogger) is after the MAF. if you do decide to do wet shot, ideally you're going to wanna direct your shot at the throttle blade (obviously) and about 10 inches away from it to give it space to adequately atomize the fuel/nitrous.
a dry shot is pretty idiot proof. just point it in the direction of the maf. ive used both setup and they both work great. depending on how big of a dry shot you use, you may have to supplement with larger injectors. in nitrous
, its all about the setup and tune to get the most out of it.