I attempted to remove the sensor again today, this time by sawing the plain head screws across the top with a hacksaw and then using a screwdriver to open them, this worked but took quick some effort.
Only to find that underneath there was no access to the internal components of the sensor at all, there is just a plastic spring loaded mechanism, which i tried to remove carefully and snapped half a notch which secured the top arm of the spring, luckily it still holds the spring in place.
The other damage ive probably done is when i unscrewed it i didn't note the exact position of the bolts, so when using hex bolts to screw it back down, the spring loaded swivel Arm at the top which slots into the throttle mechanism, creates some tension when trying to align the screws back, as it moves.
There is a 10mm difference between the centre and the edge where I think it may actually originally sit according to the marks on the gasket, which I ignored and centred it for some reason, creating some tension on teh spring loaded section. Im not sure what affect if any this will have now.
and not to mention with all the sawing the frame at the back scratched the life out of the top of my air filter box