Just did a gm wiki search on the number that is on the box of the switch I have 3125380
...GM wiki... From the 1951 GMC truck parts book
...link... After looking closely at the switch I have ,I noticed markings on the back between the fuse and resister
...ARK-LES... it is 3 position with two terminals on the back. Wiki states if for an 1951 GMC truck with economy heater.
Like I stated earlier, I installed one of those aftermarket lighted rotary switches, also used a lighted aftermarket switch for my back up b-31.
Ebay seller of the switch I purchased could of just used that box with markings and put this switch in it for sale.
