O2 Sensor Wiring - Hijack

[JeffP-Z]

I am in the process of wiring up new oil pressure and fuel pressure sensors which Ecutek has hijacked the 2 downstream O2 sensors as they are tuned out and I cannot for the life of me find the wiring diagram for the O2 sensors. Looked here but the post which had it and many others referenced seems to be gone, or missing the pic/link. I tried Nico Club but all I could find was the generic owners manual stuff. Not sure if I just didn't search hard enough or I am back in the short bus club?! Either way, its too cold outside to sit there with a multimeter searching for which is not the ground. I already know the two white wires are 12v for the O2 heater, so left is black and gray. My oil temp sensor seems to use gray for +12 and black for signal, just trying figure out if Nissan is consistent (not a common thing from my experience) or if black is ground and gray is signal on the HO2 sensors.

P.S. Anybody have any 5v suggestions on nearby sensors, like maybe one of the trans sensors?