I recently purchased a 1955 series 1, chevy half ton and it has a large hole in the top of the dash. It is located about center between the gauges. It appears to have been done at the factory or at least professionally done long ago. I cannot find any pictures of other trucks with this same hole or one with an accessory installed there.
I'm new to old trucks and new to this board. I don't know yet how to post a picture here but I can e-mail a couple of pictures if it would help to see it.
Thanks, Steve