hi, it`s easy
Use R33 loom, you will have wiring/soldering issues with AAC, VTC.
Swap tps, oil pressure and O2 sensors. Leave air regulator, FICD connectors unconnected as there is no such devices at neo.
Use r33 evap. canister, bypass r34 purge valve.
That`s all i can remember. my R33 is S2 and it now runs WGNC34 NEO with R33 ecu (now it`s powerfc).