I need to know what is required. Like, certain electronic connectors, physical connectors, and any vacuum lines.

I managed to get a BARE RB20 ECCS head for free for my NICS engine so I thought I would just swap it and it also allowed me to replace the head studs with ARP head studs.

I dug around for a bit didnt come up with much. Thats an old dinosaur ive never seen or messed with one myself. Im aware they were made and refered to as red top rb20's. Id say your best bet is to build a complete eccs rb20det. Just convert everything to eccs silvertop. As far as swapping the head and retaining your NICS just look to see if the intake and exhaust can transfered first. If not then you'll have to run all the eccs bits. That is assuming the head can bolt up and things like compresson ratio and all that are similar. Id assume you could bolt it right on and run eccs complete system. I do not know if something like timing belt alignment or if the NICS has knock sensors in the block. ....not to say you couldnt machine some into that block.

WOW, someone actually responded. I already did a f*** ton of research by reading the fsm and all I have left are the Intake Coolant pipes that go underneath. I am missing those and am wondering where I would be able to find some. Do you have any idea?

Id just thread npt barbed fittings or custom fittings into/on the block and just use soft line. No need for them to be hard lines.