How do I remove a metal carpet threshold that has no screws or nails to install a wider threshold to cover where the cat frayed the carpet?

You probably have the kind that clamps down on the edge of the carpet. It started out as a V. the bottom part is nailed down, the edge of the carpet is inserted and the top half clamped down to hold it. There are hooks on the bottom half that grab the carpet. To remove it, pry up the top half, hold back the carpet and pull up the strip.