on the maxima.org forum there is a swap for 4th gens that seems fairly easy and cheap for a first mod for me. You take the intake manifolds, iacv, egr tube guide, fuel rail and injectors, rear valve cover and coil packs, and throttle body, all from a 2000 maxima. my question is would these parts be ok from a junkyard or would it be better to try to get some if not all new? This is not going to be something I tackle for another year, just to make sure the car is going to hold up. Here is a link to a site explaining everything as well as a parts list. They disabled the drag and copy function or I would have posted it in here.
http://tatanko.boredmder.com/