I would do some looking into the pinouts from the dual board ecus ala JDM land, and the 90/91-94 ECU's USDM.
I know it has been covered at galantvr4.org, as cheekychimp was looking at working with ECMLink on his JDM wiring setup over in HK.
This is only an issue if you want to use USDM ECU plugged into the JDM harness. Most harness's you are likely finding now will likely be nearly identical to the 91+ USDM stuff, with plugs at the sensors, more wiring to the transistor pack (due to the coil interface being built-in versus the pre-facelift stuff being separated like 90 USDM stuff).
Just make sure you are getting a 6 bolt crankshaft/flexplate combination. Oh, do a little research into the cranks for the automatics, as there seems to be a sticky point lingering in the back of my mind with crank snout differences and such. Check the write-ups on RRE for import motors and maybe someone can chime in with any compatibility issue with using an automatic equipped engine with standard shift components, and that is directly related to the stuff coming from Japan.
Hell, even a call to Dan (1lowcolt that used to log in here) in Gatineau, could help out. He is very knowledgeable in this regard. Just explain your situation.
Quote:
HPAUTO
WebsiteDirections
Auto Repair Shop
Address: 1716 Atmec #2-3, Gatineau, QC J8R 3Y4
Phone:(819) 643-9489
You may get Marty on the phone too, as it is a two man show.
It is singularly the best way to shoehorn a running combination back into an engine bay. But, get the timing belt swapped out, timing components (OEM tensioner), etc, before installing it. Even the water pipe into the water pump (seal), is a great idea to do then.
Knowing what chassis the combination came from, is the single biggest issue here. It could mean the motor is 7 bolt style like the RVR/EVO stuff.