I encountered the exact scenario that you did last year with our '66 Coronet 500 convertible. Are you working on a '66 Charger? The year of the car will help me help you.
i have a new 2571-501 five button a/c switch.
i bought this for my 65 coronet without knowing it's an a/c switch and i need a non a/c switch. anyhow, it has the early part number.
i gave $40 for it and would like to get that back or trade for a four button non a/c switch in like condition. i didn't take any pics of the button side because they all look the same. i thought the "business" side would be more relevant.