Trying to install air fuel gauge.. need help!

[98chev]

i got the autometer gm performance air fuel ratio gauge and am in the process of installing it. ive got the power and ground hooked up but not sure where the purple wire is supposed to go. i believe it is one of the o2 sensor wire but not sure which one. i own a 98 1500 btw. thanks for any help

 

[Tinbender59]

left or right which ever you want to read. do not go to the rear one it will be a waist of a good meter. post cat is normally 0.6volts continious

 

[MOBS]

a/f gauges that work off the O2 sensors are so nice to have around haha.

 

[98chev]

which wire in the o2 sensor plug am i supposed to splice into? my guess would be the purple one but never know.