Final Solution-- took to local indy shop, his scanner was inconclusive, but pointed to memory was gone & needed reflash from Ford. Took to Ford, diagnosis was ECM/PCM was dead. Got remfd Cardone unit from O'Reilly's ~$160, Ford installed/reprogrammed it. Total Ford cost~$300. Back on the road, good as before. Hope yours won't be as difficult.
Thanks for the info here and encourage others to post final solution to their problems. jh