The 53-59 trucks would be the same. They have the same spindles. The earlier trucks are pretty much the same also, they just use different bearings.
I guess the guy that made the brackets patterned it after the TF trucks, not the AD trucks.
Changing to Bendix style should be no big deal. You may have to open up the top holes to 1/2". I believe they are 7/16 from the factory. Other than that, direct bolt on.
