I just inherited a 1941 Ford 9n tractor. I'm very excited to learn about it and begin a restoration. I don't have the key, but the tractor is in running condition. My neighbor and best friend recently passed away. He often used his 9N to repair my driveway. His Family wanted me to have the tractor. (What an honor). I was wondering if the keys from that era are a universal fit or do I need to get a whole new ignition switch?