Hello mate,
I have one of these wideband A/F gauges and controllers.
It is a very well made bit oif kit but i'm still in the process of fitting it so can't comment on how accurate it is etc.
Install is very easy:
Drill hole in exhaust and weld in boss to fit sensor
connect all the plugs (it comes pre fabricated so all you do is plug it togeather)
Connect power, earth and guage wires.
Matt.