I picked up a universal tractor ign switch at a local TSC to get my 49 going as its switch was kaput. It has aux/on/off/start. Since tractors lack the electrical load of an automobile I installed a 30 amp auto relay and use the key switch just to control it and run all loads through the relay. It works good this way. I do carry a spare relay for just in case. If/when I upgrade the steering column it'll get a late model lockable ign switch, one day ....
If your electrical load is lite you won't need a relay.
Good luck
Dave
