Greetings, Y'all,

I've been getting help from this forum for quite a while, but I can't find anything that addresses what I'm dealing with now. Here goes:

'99 F350, 7.3, 397K 2WD Automatic

Had rear pinion seal replaced 3 weeks ago. Immediately after picking up truck, noticed starter was engaging while driving. Drove back to shop, they said it was a totally unrelated problem. (Never did that before.) It finally stopped on its own, so I drove home. Put in Park, lever loose now, and when I let go of it, the starter engaged again (truck was still running.) Discovered that if I held shift lever up and let truck roll back until the parking pawl catches, starter acted normally. Or, I could just turn off key, but if I did that, the next time I would start the truck, it would start with the key in the RUN position. Daughter borrowed truck, and I forgot to tell her about problem, starter fried. Replaced starter. Took wrap off steering column to look for anything obvious, but nothing looked odd. Replaced shift tube, since I was already in there. Put it all back together, still started in RUN. Replaced ignition switch (not key cylinder) no change. Replaced TPS. VOILA! Starter problem solved. It started within 2 seconds after being parked for a week. Turned truck off to put tools away. Big mistake! Now it only cranks, no start, so I've traded one problem for another. RPM shows about 500ish when cranking, but no oil pressure, ICP appears to be good (no oil showing, no corrosion.) HPOP reservoir full. Would not start with ICP disconnected. (Insert favorite bad word here.) Can anyone shed some light on this? I'm ready to call an exorcist.
Thanks. Sorry it's so long.