Motorswap HELP! SR - vert DOHC KA - Sohc hatch

[Nackers]

I tried a search but I was amazed to find a bunch of threads with "DOHC SR20det swap"

Anyway, here is whats going on. I could use the help, but more to either let me know I'm going the right way or if I'm in trouble here. BTW, I have done a SR20DET swap before into a SOHC coupe, but this is just a bit more complicated than that. I'm sorry if it has been covered before. Really I am. Please read on...

I have a 89 coupe that had a SOHC motor in it. The guy I got the car from sucessfuly did a SR20DET swap into it including the wiring. I'm taking the SR20DET out of the 89 sohc hatch and putting it into my 94 240sx convertible, then taking the KA24DE out and putting it into the SOHC Hatch. My questions are these...

1. Is the wiring harness I pulled out of the SOHC hatch going to just "plug and play" with my 94 DOHC Vert?

2. I noticed in the wiring harness that in my Vert I have a plug with a larger connector. It's kinda hard to explain but from what I can tell there are 3 connectors comming off the main harness into the interior. The ECU connector, a second connector thats kinda rectangle that I believe goes to the dash, and a 3rd connector that on the SR harness is smaller than the one in my KA Vert. Do I just match up wire colors or is this needed at all? Is this the consult wiring?

3. What problems am I going to face when trying to install the DOHC motor into the Hatch? I've read that there is a connector your supposed to cut off and hook the wires to. I'm not sure which one this is.

Thank you ever so much for your help. I'm in the middle of the swaps right now (I know I got this ass backwards... ask first blah blah) and I would like to have it done by Friday night so ASAP would be more than greatly appreciated. I'm moving ahead and going to just confront problems as they arise cause I'm ignorent like that

BTW, if you have any other imput to add, please feel free as long as it's helping my cause. I don't really need "Sweet, SR vert" or "your retarted" or any of that non-sence. Thanks again!