Hi All: I have a stock "A" code, auto, /66 coupe,. My spark plugs are Motorcraft BSF 42c and the car runs good. However the plugs are 12+ years old and I would like to change to platinum if possible. The Napa site shows a plug cross reference to Autolite double platinum #APP45. Good idea? or stick with the factory plugs?. Thanks in advance. Mark