Fortunately, the LHS had the Dubro steering arms. They have the proper locating of the arm on the diameter. Drilled through easy enough, then threaded on and put new clevis attach holes ON the hinge line.
An example where the theory is correct. Thank you, Mr. Ackerman. I have all four clevis take off points exactly the same distance FROM the hinge line, and they are all OVER the hinge line. So now, the PULL side pulls, constant tension as near as I can tell, as the opposite cable slackens slightly. The travel of both elevators is now symmetrical out to the maximum, and they track together.

Can't wait to fly it now that I have this fixed.