I've gone through about 8 solenoids up to this point, and I'm carrying and extra one in the cab. It seems that they stick, then I tap them and unstick them a few times, and then they go bad.
The starter is good. It is actually the 3rd starter in the last month and a half. The original went out, and I had her towed to NTB, where they installed a new one. Then when pulling out of the NTB, the replacement starter let go let go, due to the solenoid sticking and hanging up the starter. NTB replaced it with the third one, and thought they had solved the problem with the sticking sol. But a couple of days later it started sticking again, and that's when I figured out that I have to pull the negative cable from the battery to kill the system. As long as I dont rev the engine with the starter bendix still engaged I won't burn the starter. Then I either replace the solenoid with my extra one, or take the wiring off, remove it from the fender wall, and tap it until the relay opens again and replace it.
Anyway, I started talking to people and a few of them thought that the ignition switch on the steering column might be worn out, so I replaced that, adjusted it so that all key positions would do what they were supposed to do, and voila! I still have the same problem. The starter still hangs up.
So, someone else told me it might be the ignition actuator lever that goes from the key down the column to the ign switch. But the ignition switch is working fine, so it doesn't appear that I would have to take my steering column apart to replace that part. And besides I don't think pulling the steering column is a good idea, since I am camping in a WalMart parking lot, and frankly don't feel comfortable doing it without some detailed instructions, which I can't seem to find anywhere. Either way, i doubt that actuator lever is the problem.
Anyway, after all this, the problem stops for a few weeks, then about three days ago, it starts up again. I just started her up five minutes ago, to charge my house battery and run the laptop to answer your message. Started up fine, but maybe next time the starter will hang up, and I will have to pull the neg cable, take the solenoid of the fender wall, and either bang it a couple of times, or put my extra one in. Or maybe not, since there is no rhyme or reason to when it wants to hang up or when it wants to start without a problem.
In between, I have checked all wires and grounds as best I can, and while the wiring is old, there is nothing to indicate any major problem with them.