Disc question

Just to clarify, OP mentioned "control arms" above. Only the upper control arm varied. The lower control arm was the same for disk or drum, and I recall for all years 1963-76. Except some lower control arms have a bracket to attach a sway-bar link (optional) and I recall that bracket varied between early-A and 1973+ A, probably because the later have a wider engine bay (+1"?).