There are several write ups for all of this on the old forum
sr20forum old site, but to answer your question all you need is the one you have now with a window switch. If you have the 1.6L you need to extend some wiring to get them to the correct place if you have a 2.0L you will need 2 of the plugs wired into the DE (IACV plug and Temp). Make sure you keep the wiring from the VE or atleast get a VE with the wiring. You need the all important VVL plugs from it.
There are other recommendations for VE swaps, but it all depends on what you want to spend. Biggest is going to be ECU. You either need to get a JWT, NEMU, Calum, or NISTune unless you go stand alone. If you don't you need to wire install the DE injectors and keep the DE MAF.
Tons of other stuff to be concerned about, but it's pretty much all on the older board