Hi - I am fixing my O2 sensors and need to replace at least one of the wiring harness plugs, but I have not been able to figure out which wire is which. I am using Denso with Blue (signal), White (earth), and two Black wires (heaters). Looks like the harness has Yellow/orange stripe, Orange, White, and Brown/black stripe. The first pic is the rear (I assume downstream since it's after the cats) part of the harness, the second (I assume upstream since it's before the cats-with attached plug). The upstream w/plug has had one wire already spliced into it-blue. Does anyone know which of the harness wires are signal/earth/heater/heater? I have all new plugs and need to coordinate the new splicing wires to match the Denso wiring. Anybody know? THANK YOU!