1987 Legend Ignition HELP!!!

Hey guys, my 87 legend will not start. I know that the ignition switch is bad. It has been acting up since i got it. The mechanical end works fine. Key turns to both first and second position, but does not start when u crank on it all the way over. The previous owner installed a push button start, whereas you turn the key all the way to the second (on) position, then his the button to turn the starter and start the engine. But the second position (on position) no longer turns on the dash lights or primes the injectors, therefore i can crank the start button all day and nothing will happen because there is no fuel in the cylinders. Does anyone know how to wire the ignition switch so that I can flip on a toggle switch to engage the injectors and dash lights, then off again to turn off the car once it is running?
Any help, links, or diagrams would be much appreciated!!!
~Zara