Hi, I'm new to this forum. I purchased a 2008 F150 Lariat with the 5.4 engine. The engine had been replaced by previous owner for a 2006 5.4. I never considered that to be a problem until I got ready to replace the spark plugs. When I removed the coils I found the brown boot ignition coil (8L3E-12A366-AA) installed which I believed are the correct ones for that year, however, when I removed the spark plugs I realized that the Motorcraft PZK 14F were installed instead of the plugs designed to be used with the brown coils. My question is, since it is a 2006 engine, should I buy the black boot coils/spark plug combination or just get the spark plugs for the brown coils? I don't know the difference between the coils. My guess is to go with the black coils. By the way, when I removed the spark plugs one had the electrode broken off.