On the jzx90 chaser harness there are only 2 of the 4 connectors that go to the ecu on the engine harness itself. The other 2 were integrated into the chaser's body harness.
The reason that I know, is that I ran into the same issue. I called Dr. Tweak at Phoenix tuning and explained which plugs I needed. He knew exactly what I was talking about and sent the proper ones to me.
Kind of a pain in the ass, but if you go off of the jzx90 pinout, and then match it up to the jza70 when you go to wire it, you should be ready to rock.