What kind of distributor and ignition do you have? Is it an HEI or a MSD box or what? You just need to break the 12 volt wire to the ignition with a toggle switch.
Run one wire from a 12 volt source to the solenoid. Break that with a push button. Whatever type ignition you have will need a 12 volt wire to it from the battery or fuse box or whatever you want that has 12 volts...just break it with a toggle switch.