which O2 wire for A/F gauge (BPT)

[blindfendersk8r]

3 wires on the O2 sensor, one black 2 white, i assume black is some sort of ground, which white wire do i tap into to get the A/F gauge to work right?
i know its not wideband so theres really no point, i also already know im runnin rich, but whats the point of the gauge unless its plugged up??
plus im not sure how rich/if im actually rich up top (still to rev to high, no Tclamps and freshly started motor)
help apreciated

[ariesdude]

Black - O2 signal
2 Whites - O2 heater

You tap into the black wire

[blindfendersk8r]

thanks alot, ill hook it up tonight, but i just took the charge pipe off to be rewelded so i wont get to start the car...
i would have never guessed the black wire...