I think this post has got a few brains ticking away and has helped me to understand a bit more than i did in the first place. ( I still need to know more )
So Also Martin Tribe was 100 % correct as well with his Astra X20XEV,
And I was right in thinking that they work the opposite way to normal but only on some vehicles. ( not the one in question though )
Anyway. Thats sorted that one out so far. All we need now is some decent manufacturers information on which sensors work which way and what colour wires do what. www. Lambda sensor . com has some decent info but doesn't really touch on the subject of all these different variations.