Carl,
You can google Old Air Products Ft. Worth, Texas to look at their line. Here is a couple of shots of the unit in a 49 pickup. There is one more outlet on the left side of the steering column.
http://s32.photobucket.com/user/coilover/media/dans%2049%20002.jpg.html
http://s32.photobucket.com/user/coilover/media/dans%2049%20011.jpg.html
I did a 51 GMC with the radio grill as the outlet/diffuser and it didn't keep the cab nearly as cool; even put some angled baffles to route the air to the sides. This was before insulation/deadener like Dynamat so now who knows?








Evan