[Captainfab]

To my knowledge the '73-'87 front suspension crossmember is basically the same as the '63-'72 crossmember. The only difference that I can think of is the '73-'87's use a larger diameter U-bolt to attach the LCA shafts. So consequently the holes in the crossmember are larger to accomodate. The older crossmembers can obviously be drilled out. I would recommend upgrading to the later model larger LCA shaft U-bolts.