K-Member question

On a cost perspective, use everything you can off the '73 and up car. It all bolts in. Use the steering box as well if it's the same style as yours, the pitman arms are 1/2 the price of a '68-'72.
I did this swap last year on my '69 Valiant 2 door post and it works great. Twice the stopping power or more than the 9" pos set up in there before. And easy to get parts as well.:cheers:
Good luck.
Tom.