I foolishly cut off my Lambda sensor when I stripped my car, and need to re-instate it, where does the wiring run from, as I'm not sure where to start looking.

Car is a 2000 Mk5 Fiesta.

Alternatively would it be advisable to take the opportunity to install a wideband lambda sensor? The basic spec is cammed 1600 Zetec SE on ITB's and the caving to around 8k with an Omex 600 ecu.

Could I run a wideband with the ecu, or would I still need the standard sensor?