The original 55 1st ignition switch is a OFF/ON switch.
It has three terminals on the back side.
One terminal is for power from the ammeter.
The other two terminals receive power when the key is switched ON.

Original 55 1st ignition switch
https://www.classicparts.com/1954-55-1st-Ignition-Switch-Original-Style/productinfo/53%2D407/

Lock Cylinder
https://www.classicparts.com/1947-66-Ignition-Switch-Cylinder-w_Key/productinfo/53%2D475/

More info in this THREAD

If you could provide some picture of the switch, front side and back side and how its mounted in the dash.
Would be helpful.