Here is an update.
I cleaned the battery and ground contacts, which were a bit dirty but I have seen worse. Anyway they are clean as a whistle now.
I then test drove the van about 7 miles, and parked it with engine idling in a shaded parking lot. I opened the hood and started wiggling wires, just to see what, if anything, would happen.
When I wiggled the wiring leading up the the Automatic Shutdown (ASD) relay, the van missed. I wiggled the wire again, and it missed again, this time almost stalling out completely. I drove the van back to my garage, and the engine missed several more times on the way, but I got it home.
The memories then came flooding back - I had replaced this ASD relay almost two years ago when it was giving me similar problems. The connector was broken or burnt (I can't remember which) so I cut the connector off and put individual blue connectors on the end of each wire and the secured the wires to the appropriate terminal on the relay (as verified against circuit diagram and consistent with my scribings). The van ran like a champ after that.
Aaaanyway, back to the present. Once I got my van back home this past weekend I checked some of those connections I had made to the base of the ASD relay, and two were loose, one on a yellow wire and another on a dark blue wire. The yellow wire one was particularly loose, the dark blue one was not as loose but still suspect. I put on new blue connectors, and reattached the previously loose wires. The other two wires felt tight and secure, so I left them alone.
I electrical-taped everthing back up and retested. The van idled fine and would no longer stall when I wiggled the ASD relay wiring.
I then took the van for the 45-minute drive test. Sure enough, once I had almost completed the trip, once I got to back to within a few miles of home again the van started stalling. Ugh.
I got it back home again, and shut it down, and went in to get a (non-alcoholic) drink. I went back out to the van, and started it again. It ran for a few seconds and then stalled. I could not restart it. The engine would rotate, but would not fire.
I undid the doghouse, and attached a spark checker to one of the plugs. I attempted to restart again, engine would rotate but not fire. I noticed I'm getting no spark. I then checked to see if I could hear the fuel pump hum by just turning the key to the RUN position. Nothing.
I figured the next logical thing to do would be to go in, get another (non alcoholic) drink and watch some sports on TV in my air conditioned den. Surely that would help my van.
I went back out after an hour or so feeling a whole lot better. Surely the van would start. And it did. Fired right up. I revved it left and right and it sounded like it wanted to go out and drag race some C6 Corvettes. I drove the van a few miles and it started to miss again. So I turned around and went back home.
So, alas, the van still sits in the driveway. I no longer trust it and I am out of ideas. Do you all have any suggestions as to what I should check next? Thx, Pop