Good research Red, you seem to have most of the answers.
I will not claim to know all the cross-overs with these parts but I did take a 73 and up "spool type" K frame and installed it into my 68 B'cuda.
I bolted-on all the earler parts and it worked-out nice.
I do remember looking at all the different centerlinks and idler / pitman arms, I used all the parts that gave me the most oil pan clearance, basically the stuff with the most "drop". The arms were the 68-72 ones, the centerlink was "out of the pile" but everything went together fine and the geometery is spot-on with the ride height set pretty low.
I even checked bumpsteer and it's minimal.
I do remember the later (73 and up) stuff, it did not have as much drop to the center link (a real flat looking centerlink) and the arm studs point down, nuts end-up on the bottomside of the centerlink.
My current set-up has the through bolt idler arm, the small spline steering box pitman arm (manual 16 to 1 box) 11/16 C-body tie rods and that deep drop centerlink with the arm nuts sitting on the topside.
Over the years, the car has been into two different alignment shops, both times it aligned without problems and the mechanics really loved the fact that the fenderwells are out of this racecar, it was the easest A-Body Mopar they ever had to adjust. They could get right at the upper A-arm cams without bending over!
