How To Hotwire 90 Sunbird

take the panel under the steering wheel off and find the ignition harness. Twist the all of the wires from the ignition harness together (these are the thicker wires going to the steering wheel) except for the starter wire (starter wire should be yellow), touch the starter wire to the twisted wires until the engine starts, if you leave it there longer it will mess up your starter. to turn the car off, untwist the wires. The car will run but you will still have to use a key to unlock the steering wheel (I'd recommend stripping part of the wires and attaching extra wires instead of cutting the wires that are already there, so you can still plug the ignition harness back in)

This should be the same for most GM cars without extra security.