Bought 02 sensor, but can't find where wire harness is. on 1998 Mitsubishi Diamante

Wires from 02 sensor go to a plug at bottom of car. I removed plug and wire continues through hole and can't find harness.

Asked by for the 1998 Mitsubishi Diamante
I think you have to pull up the carpet on the passenger side next to console. The plug should be there.