I think I see you are not looking at the type Dan is speaking of. Which has a position that has a momentary spring loaded position for non foot/solenoid start. I think you are looking at two position, two terminal and three terminal older ignition switches. It really really really makes no difference which you get of those.
The 39 and 53 are wired the same. Foot start. 6V
1. Switches are designated by positions and by number of terminals. (and operation, I.E. rotary, lever/toggle, slide, push button, etc)
2. A two terminal, two position older switch is just OFF position and ON position.
3. At some point a three terminal, two position and a three terminal, three position came along.
4. The three terminal, two position is... ALL OFF and ALL ON.
5. The three terminal, three position is OFF-ALL ON-ACC ONLY
In simple original wiring, you will be wiring either type with one wire from the ammeter to an IGN sw terminal. Then two wires from another ignition switch terminal to the gas gauge and to the coil. The ACC or a third terminal will not be used and no one will know but you.
You are in the right place here, the membership pool knows everything you will ever want to know about your 39/53 and glad to help with any question.
Just remember, you are showing OLD switches which can be worn/internally broken or corroded or both and they don't look like they are very easily torn apart to clean, but can be done. They would need a continuity test and voltage test if they are pricey. If cheap, take a chance I guess. Some of that stuff does not last 86 years. Trying to use preowned/NOS switches, tumblers and old/dual use key may be driving you too hard unnecessarily. The "O" in NOS stands for "OLD".
If you open an old one up that does not have a key, you may be able to release the tumbler form the "back side".
Last edited by bartamos; 09/08/2025 8:24 PM. Reason: clarification
