AEM UEGO question

[1NonlyAccord]

Just got my gauge kit,reading the instructions and of course it has the normal red-Power wire, Black-ground wire, THen they have white-analong output that needs to be hooked to any auxiliary unit that accepts 0-5 volt input.
where do i tap that wire into? (99 accord OBD2)--phearable.net chipped ecu w/ harness.)

im going to run the Blue-serial output over to the ECU location and leave it unhooked and the tunner can do w/e they need with it.

Thanks for looking.