If I recall correctly the first drama was about 1966. In Baltimore, actress Joyce Holden played Potiphar's wife. The details are fuzzy after all these years. Maybe someone else can shed light.
Did get to mouth some parts over the years and you would recognize my voice in several of the first dramas released on tape for the masses. Prior to that they didn't want anyone having copies of the tapes sent to the conventions for use during the 'performances'. The convention office was always certain to get the tapes back and return them to Crooklyn. I never understood their fear of tape recorded copies of the programs in those days, other than control.