FULLY SOLVED! Not by any genius on my part, but a chance placement of the neutral switch swing arm. I had been trying to locate the harness, to absolutely NO avail, when I decided to give up on that path. Before re-mounting the switch, I gave the swing arm a twist and tried the key. The reason I did that, was that earlier, when moving the arm back and forth and trying to start, there was a single click. It didn't seem to solve the problem, but it was something besides dead.
I wanted to hear that click again to see if it would lead me on another solution path. In the effort to place the switch arm in the place to get the click to happen, I hit the sweet spot and it started!
I needed to mount the switch, so I had to turn the engine off. I mounted it and tried again, having tied the arm all the way down. No go. Then I released the arm and again tried different placements until it started again. It was then I *realized* the error of my thinking. The neutral switch is meant to work in the central neutral position of the gear handle. Either end of its travel is a cut-off position.
Thinking is hard. :ashamed: Good thing it worked out, my wife was beginning to call the tractor a lawn ornament.