K-Member question

If you use the 73 draglink you'll need the steering gear and pitman arm since those are different too. The pitman and idler you have now ( 67 ) load to the drag link from bottom up ( grease fittings toward ground ). The 73 is just the opposite.
It would be easier to use the steering gear, pitman arm and draglink from the 67 and buy a 68 idler arm.