I missed out on the most obvious option, pull the fuse!
So as a quick test i popped the Injector fuse out of the engine bay and replaced it with fly leads to a switch with an inline fuse, i then started the car, no warning lights is always a good sign!
Flick the switch off and the car stalls, flick it back on and it starts right up, excellent!
Then i re-ran the wires through a grommet in the fire wall and up to my gear shifter, where i taped the switch:
I then stuck my gearknob (aka tennis ball) back on top (you can just see the switch poking out from under it):
My first test drive around the block shows that it works perfectly, except for one problem, because ive tapped in to the injectors after the ECU the ECU is still sending the signal to fire the injectors and as such my fuel usage gauge still thinks im using fuel, will a scangauge have the same problem? can anyone think of a way to fix it so it shows actual fuel usage?