Let me clarify something, if only to see if I've got it straight: The building on Hollywood Boulevard from which Jimmy Kimmel is broadcasting is referred to as the El Capitan. It's actually a TV studio that's part of a complex that is still being developed around the El Capitan Theater, which has been a fixture of Hollywood since it opened in 1926, right across from Sid Grauman's famous Chinese Theater. The following year — over on Vine, just north of Hollywood — another theater opened. This one was called the Hollywood Playhouse.
The El Capitan on Hollywood housed plays and then movies. In 1941, Citizen Kane had its world premiere there, and then the theater closed for remodeling, reopening soon after as the Paramount Theater. In the meantime, the Hollywood Playhouse had segued from hosting plays to network radio programs, including Baby Snooks and Lucille Ball's My Favorite Husband. When the name became available, they redubbed this theater the El Capitan, and it later became an NBC television facility for shows like This Is Your Life and The Colgate Comedy Hour. A lot of the celebrities who were surprised on This Is Your Life were snared at the Brown Derby restaurant near Hollywood and Vine because it was just down the street. The celeb could be "caught" in the opening segment and then quickly driven up the block to the El Capitan during the first commercial.
In 1963, Jerry Lewis launched a highly-promoted, prime-time 2-hour live talk show for ABC on Saturday nights. For it, the network purchased the El Capitan on Vine and completely redesigned it, installing all new seats and equipment in one of the most expensive facelifts in Hollywood history. They also renamed it the Jerry Lewis Theater. The program was a spectacular failure and it left ABC with a 2-hour hole on Saturday evenings and a theater which they'd spent millions to acquire and refurbish. They solved half their scheduling problems by creating a variety show called The Hollywood Palace, which filled one hour on Saturday nights for several years. It was done from the theater on Vine, which they then renamed the Hollywood Palace.
After the variety show was cancelled, ABC rented the facility out to anyone who wanted to pay for it. For a long time, Merv Griffin's syndicated talk show was done there. Around 1975, Merv was tossed out. The way I heard the story, ABC needed a home for some new game show. Merv, who didn't want his operation displaced, offered to pay the difference if the game show would go elsewhere, but there was a network corporate policy that said that an ABC show had to be given preference over some non-ABC show that was merely renting space. Merv went down the street to a videotape facility called TAV, bought it and moved his show there for the rest of its life. A video engineer I know told me this tale and said it sealed the fate of the Hollywood Palace. They lost a lucrative long-term tenant to take in a quiz show that only lasted 13 weeks. The theater then sat dark so long that ABC closed it down as a videotape studio and finally sold it to a businessman who gutted and restored it as a nightclub. In 1982, it opened as The Palace, which is its current identity.
In 1989, the Disney folks bought the very dilapidated Paramount Theater on Hollywood, right across from the Chinese, and began retooling it into a state-of-the-art theater as part of a new entertainment complex. Kimmel's show comes from the TV studio which now adjoins the movie theater.
So the El Capitan became the Paramount and then went back to being the El Capitan. And the Hollywood Playhouse became the El Capitan and then the Jerry Lewis Theater and then the Hollywood Palace and it's now the Palace. I think.