I wish I knew more about this. Vincent Terrace, in his
encyclopedia of TV programs, lists all the announcers
for NBC's movies, but not ABC's or CBS's.
The only other person I can think of who might have
been the announcer would be Fred Foy, who
announced ABC's "Wide World Of Entertainment"
(and "The Lone Ranger," "The Dick Cavett Show,"
and the short-lived game show "The Generation Gap").
If he's not your man, then I give up.