Yeah, sorry I did mean to update this thread as I managed to get the car finished. For the emissions and just so it was nicer in general I decided to change the HT leads, spark plugs (turns out the ones in there were for the wrong engine hah), dizzy cap, rotor arm and did an
change as well as changing the lambda sensor.
This was all easy except for the lambda sensor which was a bit of a mission. I have the E type engine and space around the lambda sensor was pretty minimal, so I couldn't get a spanner round it (nor did I own a 22mm spanner) or a socket due to its length and the connector at the end.
What I had to do in the end was cut of thee connector via the wires and hacksaw the actual sensor part in half, or at least enough to get a deep socket round it and then extract it that way. Thankfully putting the new one in was much easier than taking the old one out as it was possible to use the open end of a 22mm spanner on the nut.
Most importantly the car then passed the emissions test during the MOT, but sadly the garage found new things to fail it on - the ¤¤¤¤¤¤¤s! haha. Also I wasn't actually able to take advantage of the companies who sell aftermarket sensors as it were because I wasn't able to find the engine code anywhere and the part number I gave them didn't match up with their stock. So in the end I had to buy from a Renault dealer for 111quid
Wooa long response, hope it helps. Thanks to all who offered advice to me on this.