Is it possible just like a kill switch i know there will be a **** load of wiring but, can it be done or has it been done? Just wondering cant be to safe these days

 

Yes it can be done, but why not just install a switch on the ECUs control line to the PGM-FI Main Relay, it is a low current ground, so requires only a small 1A on/off switch, and only requires you to cut the lead and install the switch some place between the ECU and the PGM-FI Main Relay, you may have to extent the cut wires to the switch, depending on where you make the cut and where the switch is mounted.
Or better yet, install the switch on the ground, [ground for injector relays coil] to the PGM-FI Main Relay, that will cut power to fuel pump the injectors the ECU and some sensors, also a low current ground. 94

 

I already have a pump cut off switch, ign cut off, and power cut off. Looking for something to cut the engine harness off even if they get past the immobliazer(i cant spell right now sorry) or am i just been off haveing those 3 cut off. also have a gps system and another alarm so i have 5 systems not including qucik release steering and a boot.

 

LOL. pretty soon your going to need a check list to start the car.
I think you probably have enough "layers". 94