Car heaters (and radios) were optional on American cars all the way up thru the 60's! Arvin used to make both (and is still in business, electronics and automotive).

My Aunt used to work for Motorola in some military division. Last year I visited Chicago and contacted Motorola seeking a tour of the museum. Never got anywhere with them as my contact person kept passing the buck to someone who never would contact me. The bums.

Anthony