It looks like El Dorado opened in 1968...

By the mid-nineties there were only two Gardena poker palaces left--the Normandie Casino, which had opened in 1942, and the Embassy Club, which was torn down and rebuilt as the El Dorado Club when George Anthony bought it in 1968.

From this web page:
http://www.joebobbriggs.com/vegasguy/vg20010302.html