I've heard an aircheck of Huckleberry stating that it was Chip Chip, and that the reasoning for playing that song first was that they wanted to chip away at KFXM's ratings.
The comment below stated he heard from Bill Watson? that it was Johnny Angel. I know Johnny Angel was the first number one song listed the K/mentertainer (See March of this year for a picture).
Are there any comments from people who were there, or heard the opening broadcast?