Correct heater switch if you are looking for it is a version of this (several colors and labels, Air, Def, Heat). Not Ark-less or other rotary types they are not original to these trucks. They are usually marked Delco-Remy or Cole-Hersee. These switches come with both the Air-Flow and the Recirculating as I have owned both as NOS kits. I have owned or parted 30 of these trucks and on the near originals this is always the switch type found. There is a sound reason for this if a truck was accessorized with Fog lights the two switches go side by side and they are close together under the left side of the dash see fog switch picture, there is not room with a rotary.
http://www.flickr.com/photos/advance-design_parts_co/8129327386/in/set-72157631868452754
http://www.flickr.com/photos/advance-design_parts_co/8129466604/in/set-72157631868452754
Here is a NOS view of the defroster referred to above, your recirculating heater should be the same.
http://www.flickr.com/photos/advance-design_parts_co/8129330842/in/set-72157631868452754

Last edited by Brad Allen; 09/21/2013 9:51 AM.
1950 Chevrolet 3/4-Ton 3600
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