From one of Randy's previous posts: "...if you want "stock" platinum heat range in a Motorcraft, it's a AGSF-32-PM which is now a SP-493, if you want the same heat range in a copper core, get a AGSF-32-C or SP-447..."
motorcraft sp493. its the correct spark plug for your vehicle. btw as was stated above most if not all dealers use the new spark plug numbering system.