push start & stop button

You would have to have 2 buttons. One to power the ign side when pushed. The other to energize starter seliniod when pushed. A toggle switch with a separate push button would work also.

If your thinking a one button does all kinda thing with a key fob in your pocket like the new cars now a days cant help you. That's some high tech stuff way over my head.

 

an O2 Century why doesn't the key work??
is it a show truck

 

You need to install a toggle switch into the hot wire that supplies power to the ignition switch. And a momentary push button switch into the line that activates the states solenoid. It not that hard to do... A little bit of time with a test light to figure out which wires have power through ignition switch when key is on... these will all be wired to the toggle switch, as well as the solenoid wire with the push button between toggle and solenoid. I have an '89 F-250 that I plan to wire this way when I get time. Currently the internal mechanism behind the ignition switch is operated with a screw driver, then I have to cross 2 terminals under the hood with a screw driver to activate the starter. The key switch went hay wire on me a few years ago and I havent gotten around to rewiring it yet. It would be adviseable to hide the toggle switch so its harder to steal the truck... Since it no longer requires a key.