Thanks Dan, The guy at the salvage yard thought they came off a 47 but he wasn't sure. When I saw them laying there my first thought was hey bumpers for my truck! Twenty bucks apiece I wasn't going to leave without them. The stamping on the back side has GM-D but I haven't found anything related to the stamping. It looks like from the pictures the AD's have more of a curve out towards the end. I guess when I get far enough along to mount them I'll know for sure. Thanks again.
Gary