Sorry, but whoever told you this was confused. There are basically 3 sets of A body steering linkages, 63-66, 67-72, 73-76 each with their associated K-member (67 pittman arm is unique). You can't mix between the different types.
Partly incorrect. No mix-match on steering linkage between 66-down and 67-up, BUT 68-72 and 73-76 can be swapped around if you use all the parts form the same setup. 67 is limited by the single stud idler arm.
