OK. I can now put this item to rest. Some of this is on me though so crow eating is in order.
Turns out that the fairly new ignition control module was toast. I repaired that part a year or so ago, and when doing so, I did no put the heat sink grease on the back of it. Turns out it eventually gave up the ghost. What was confusing is that it had good days and bad while failing. I am still a touch frustrated that the mechanic that had been looking at it, could not really drill down on what was going on, and had repaired things that did not need repairing twice. Oh well. Now the truck is running and I am smiling. Now I can watch the last episode of Off Road Alaska, and smile knowing that I own a running D-90, and not be bitter like previous episodes.