This is just a historic note: I heard one source say actually LBJ did not even have to be sworn in again. His swearing-in as Vice President somehow fulfilled his being President should something like this happen. Also, the Bible that was used in 1963 is missing, something like that would go into the National Archives or somewhere like that.
Something I hadn’t realized until today was that there was no Vice President, until LBJ was elected and was inaugurated in 1965, when Humphrey became VP.
Thanks. Interesting.