I don't have the answer to your prolem... but do you know how the bracket attaches to the bed? There are special holes through the bed angle and wood that attaches to a angle to the bottom of the bed. And also, do you know how the bracket attaches to the side of the bed? I would suggest try finding a dimpeled finder. Once in a while you will find one on e-Bay. Good luck!
P.S. There is a little more involved than the diimple. Do you have the bracket? How does the bracket attach?
1953 was the first year for this option on the AD"s. If you have a 53 (without this option)or a pre 53, then you will have to do modifications to the bed to make the bracket to fit, like driling holes in the proper places.
Here is a pic of mine
