I know it's been a WHILE, but I finally got around to working on this some more. I chased ground wires in the harness a while, but after disconnecting two and still seeing a good connection to ground, I elected to cut all the injector ground wires and run a common wire from them to the cockpit, through a switch, and back. This works. The truck starts with the switch in "on" and won't with it off. Haven't road tested yet, but should be nice going down long grades or coasting up to toll booths...assuming the PCM doesn't complain about injector flow.
