Is it possible that a 1973 A body K member

You need to use the 73-6 center link,each k frame had their own. The 68-72,the 73-6 and 67 center links are specific to each grouped k frame.

You can use any center link as long as you use the same vintage idler arm and pitman arm. The 67 was unique because of the way the idler arm mounted to the K frame.

When I swapped from /6 to the 360 in my 68 I used a 73 spool mount k-frame with the 68 idler, center link and pitman. Later when I converted to power steering I used the 73 steering box that has a larger shaft and I used a 73 pitman, center link and idler.