I guess what you are calling an AD radio is the US made model for the 1947 to 1953 GM truck. Your Model 48 is a Canadian radio made for the Chevrolet passenger car 1942-6-7-8, Pontiac 1946-7-8, Oldsmobile 1946-7 and 48, 1947-8 Chevrolet truck, Maple leaf truck and GMC truck. It has adjustable controls that move for both spacing and angle. It uses a different dial glass when mounted upside down in some of the cars. The radio has a dual audio output design and gives twice the output power of the US AD radio. It will also fit all 1947 to 1953 GMC and Chev trucks.
I have the manual with all the various mounting details if you need information.
