For the VG30DETT you need the VG30DETT ECU. R33 ECU for the RB26DETT will also work on R32 RB26DETT's.
Yes, crossmember needs to be notched, RB25 oil pan (or custom), and exhaust manifold for clearance. You will have to make your own p/s lines, radiator, FMIC, and IC piping.
UPDATE: Since I haven't had time to finish it, I dropped my Z off to Alamo Autosports in Arlington, and they are finishing the swap for me. This house is taking up ALL of my time (what little free time I have). Updates to come.