I declare this phrase was first used (uncredited) by someone, somewhere in the South as they were driving some old American metal, shifted it into 2nd gear, nailed it and yelled "Giggity giggity."
As Jackie was driving her 1970 GTO down Buford Highway, she dropped it into 2nd gear and gleefully yelled, "Giggity Giggity" as her passengers were thrown slightly back into their seats and her challenger was left in the dust.