weird starter problem

This isn't really a question because I already figured it out. Just sharing.
In my 4.2, the starter motor sometimes ran on after the car started. The solenoid was gunked up, and I had an exhaust leak (fixed with a bolt and a Disco heat shield). But the problem persisted, even with a different starter/solenoid. I've been swapping a Bosch and Lucas starter, rebuilding whatever was out.
Also, sometimes the truck wouldn't start at all (dash lights on, but starter wouldn't even click). Everything seemed to be worse after running on the freeway.
Anyway, it finally finished breaking. Turned out to be a bad ignition switch (the electrical part that clips on the back). The ceramic was busted up, and a sliver got wedged under a vital copper strip.
It just takes a couple minutes with a screwdriver (to pull the plastic dash stuff above your feet) to check this. The switch pulls right apart.