Motocraft spark plugs and coil

Use what the dealer's parts department people recommend. That is what their mechanics are installing. Part numbers are always changing to reflect improvements. Ford has had a lot of trouble with spark plugs being spit out of the holes. The improvement could be nothing more than revised thread material to reduce the occurrence of that problem, or there might have been some change to reduce the accumulation of carbon deposits from the fuel formulations in certain parts of the country. Aftermarket manufacturers make similar improvements and revisions, but they usually retain the same part number to avoid confusion.