Thanks for the referral Boosted Z31
As for swaps into an NX2000 a GTi-R is a direct bolt-in with only a few changes to the wiring and the oil pan for a perfect fit. The only problem with the NX2000 is that when you install a front mount intercooler the car tends to overheat more readily than an SE-R b/c there is no grill on the NX only the front air damn. You might want to enlarge the opening in the bumper for increased airflow across the core and also to the radiator. I highly recommend you get a NISMO GTi-R radiator in order to properly cool the engine during hard runs.
I have a good source in Florida for *high quality* clean SR20DETs that come complete with everything you need. If you need any advice on parts prices etc...feel free to e-mail me at jwhitely2000@yahoo.com or call me at 813-546-3524.
Good luck