Here are scans from two stereo slides, circa 1956.
The Opera House is one of my favorite buildings on Main Street. There is not too much about it that is exceptional - until you get to that wonderfully ornate pediment! It looks like the top of a Chippendale desk. The masks representing comedy and tragedy are beautifully sculpted, and it all feels very authentic... a real tribute to the craftsmen who built Disneyland with such care and artistry.