Early Shackle Plate 244163 is tapped for 1/2" BSF. No Longer Available. (found on Series 1's and 2's up to suffix A)
Use later 537686 shackle plate, tapped for 9/16" BSF and shackle pin 537740 to suit.
Both early and late type shackle pins (bolts) were 9/16" in shank diameter, only the thread sections differed.
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