Carrie Underwood is a perfect choice to replace Katy Perry as a judge on American Idol — she knows the show better than most stars — but fans will be surprised to learn that she was not showrunners’ first pick. Despite competing on the show and winning Season 4, the ABC network had their sights set on another A-list singer: Miley Cyrus. “It’s well known internally that Miley Cyrus was the network and the producers’ first choice to replace Katy, but topping Katy’s already-high salary was never on the table with Miley,” a source at ABC says. Underwood is reportedly earning half the salary that P…