Rutherford did have a god-complex, a sense of being chosen by God.
Ruthford's reasoned that as Jehovah was using the Watchtower to transmit truth to the people, and as he was the president of the Watchtower, then Jehovah had selected him directly.
Rutherford thus believed he was chosen directly by Jehovah himself, who then conveyed spiritual truths to him via the angels.
And being chosen by God, Rutherford thought it was only just to live like King David, accepting gifts, liqour, Cadillacs, homes(many, Beth Sarim was only the most famous of the residences Rutherford enjoyed)
Based upon what he wrote, and how he lived, we can safely say that Rutherford was delusional, he really believed what he wrote!
--VM44