Some of my suggestions:
Try ACL gasket kits
I would ditch the Power FC for a Vipec or maybe a haltech….but it depends on the tuners you have there if they are unfamiliar with these products the result wont be as good, so maybe ask your tuner of choice what he likes to work with.
The Turbos have internal wastegates, no need to upgrade to external
No need to upgrade fuel rail
Don’t remove the 4wd fuse on a R33 GTR, they have a preload to the front diff so they are never truly RWD, if you remove the fuse you will prematurely wear the transfer case, The R32 is the only GTR where the fuse removal trick works
The Non V spec diff to my mind is better being a proper mechanical diff, maybe get it shimmed?
For suspension look at the Sydney Kid group buy in here and get something similar
The intercooler should be fine
The wheels you are looking at might be Rays TE37s??