I would estimate this house goes back to at least the 1940's given the architecture even though others have it opening in 1955. From what I can gather, it opened and closed again over the years before turning to porn in the 70's.
Supposedly it was remodeled and re-opened after that as a "legit" house but I am not seeing any ads related to that. There is a building that still stands at the location that could be the old theater with some drastic updates. The following is a link to a YouTube video about the theater.