It is a .pdf document and it should be available from a Nissan dealer also.
Someone sent me an ECU they bought of eBay that was supposed to be for an 82ZX and did not work. The JECS # on the outside of the case matched with the list but the number silkscreened on the PC board did not match the case number. It looked like it was for a Mazda and low and behold it actually did work in a Mazda. I never went any further with this as the Mazda got hit by a deer.