The first is wear on the rod as it passes through the bushing on the bracket. Strategically placed shims confirm my suspicions, I've found the remaining slop. Now what to do about it. Again pulling off the rear shift rod, I can quickly see asymmetrical wear on the rod where it passes through the bushing. Looking at the pivot ball, two flat spots stand out.
Further wear is obvious on the end of the shift finger and parallel rails on the cage.
A friend who is a welder by profession offered to see what he could do. He filled in the wear on the rod with brass, filed even the wear on the cage, and built up the flat spots on the pivot ball and shift finger. A little final sanding and filing and back it went into the car. Most of the vagueness is gone. Each gear has a distinct gate.