Thanks for the fast reply and the info and good links.
Applejack successfully completed it's run, computer restarted back to same gray screen with logo and spinning gear.
Rebooting in Safe Mode leads to same point, no further. The links you provided indicated gray screen is likely caused by peripherals, 3rd party devices. None are installed or connected.
Right now, am just letting the gear spin away. May leave it like this a while.
Other ideas welcome.
Rick in Maine