I'll show you how to wire in a push button ignition and an engine kill switch in your car. It's easy, as I have done all of the puzzling and figuring for you. It should take between one and two hours, depending on how fast you can take apart your dashboard, but could take considerably longer. This project cost me like 25 bucks for a soldering iron, wire, one relay, two momentary buttons, and a switch. If you have some of these it will be cheaper. Either way, this is a small price to pay for such a cool feature.
Step 1: Gather Materials
One Single Pole Double Throw Relay (a SPST normally open will work as well)
One Momentary switch, Normally open (toggle or button)
One Single Pole Single Throw Switch (toggle or button)
Wire (I used 18 g)
Other various tools
Be sure that whatever momentary switch or button you get is a normally open, momentary switch.
anything else will not work for what we need.