Figured it out; will post in case anyone else is having this issue:
Unplugged printer.
Reinstalled the driver from Canon (for the umpteenth time ha ha) "mac-UFRII-LIPSLX-v10191-06.dmg"
Plugged printer; it lit up
For no reason, unattached then reattached the USB cable bet printer and computer
In System Preferences, Printers and Scanners:
I could still see the printer icon as I had seen it before (kinda generic printer image), and knew this wouldn't be sufficient, so:
I selected the + to add a new printer
From the Add menu, I selected "Canon MF4360-4390 UFRII LT" via USB (as I had before)
Here is the step I had not done previously:
At the bottom of the window is a selection "Use" with "Choose a Driver" pull down.
From the pull down list, I went to "Select Software ..."
From that pull down list I selected "Canon MF4360-4390" then OK
Upon the return to the Add box, I clicked on Add
I noticed that the icon image for the printer changed to look more like the actual device
I deleted the previously installed driver for the printer
It now works. I have no idea why I had to do this manually, but so be it.