Denny,

They are original and shown in some of my owners manuals (trucks) with the directions as outlined above. Here are two pictures from factory films one is a 1949 version (Car) the other is a 1950 version (car) In these films a big deal is made in comparing the ease of one key in the Chevrolet and multiple keys with other makes. I don't know exact years offered other than what I have here so far. I will attach the truck manual references tomorrow as I have all the original 1947-1955 1st manuals for both U.S. and Canadian models. I have pulled this style of switch from 2 of the AD trucks I have owned. The body is the same as the other style the only difference is the insert with the tumblers.

http://good-times.webshots.com/photo/2607372260102454676FzTASw
http://good-times.webshots.com/photo/2290306320102454676gyGwDP
http://good-times.webshots.com/photo/2606690220102454676vKlZKv

Last edited by Brad Allen; 04/06/2011 7:21 PM.