On my 69 bird, I removed the rear leaf spring shackles, blasted, and painted them. As I go to reassemble the shackles I notice 2 of the 4 parts have a S stamped in the center of the shackle. Does anyone know if both shackles stamped S go together and on which side, or does one stamped S go with an unstamped one? They fit either way. I couldn't see the S on tear down or I would have made a note.
Anyone have an idea?

http://i793.photobucket.com/albums/yy213/colekc5swi/20141125_152748.jpg

Oh I know it won't matter to many if this detail is correct, but it does to me.