CBS Ousts Taylor as Its President; Paley to Yield Chief Executive Post
CBS Inc dismisses pres Arthur R Taylor and names John D Backe to succeed him; William S Paley will relinquish chief exec post in Apr, but will remain as chmn; Taylor's departure is linked to personal conflict with Paley; surprises Wall Street because of corp's continued earnings gains and Taylor's irreproachable record; pors of Paley, Backe and Taylor (M)