Thanks for the help.
I called TCI, and talked to the tech guy, and he said that the play in the upper control arm is how you adjust caster, by tightening the nuts differently on either end of the two holed mounting shaft, this moves the arm fore and aft, keeping the arm mount parallel to the frame.
There is about 3/8" of play between the inside of the "yoke" bushings and the two holed mounting part.(See my link to exploded view, above.)
You say that canting the upper control arm is the correct way, now I wonder if I should just tighten down the nuts on either end of the shaft, removing the play,and cant the upper arms in the slots...