No the 57's are the second series truck, some things on the chasis are different. On the AD's the leaf springs mount directly underneath the frame rails, so the shackle mounts are a different style. On the 57's the leaf springs mount on the outside of the frame rails. On the front eyes of the rear leafs its just a pin, not a bolt. There isnt any place to put a rubber seal. only the rear eyes use the rubber seals on the shackles.
http://www.lmctruck.com/icatalog/ca/full.aspx?Page=84 ok dont know how to do a hyperlink but lmc's catalogue shows a pretty good picture
