Hello, I am John, a Ford dealer technician.
I hope I can help solve your problem quickly and accruately.
To remove spark plugs you first have to remove the coil on each plug. This is located on the top of the valve cover. The spark plug is directly underneath but it takes a unique spark plug socket. You should be able to pick one of these up at your local parts store. Tell them you need a 5.4 3v spark plug socket. Here is a tip to help you out. Get the truck to operating temp first. Then let sit for an hour. This will get the engine at the right temp to remove the plugs. It is common for the plugs to break off in the head then you will have to take to a mechanic with the specialty tools to get it out. This warming procedure helps prevent this. Do one side completely then warm up again and let cool for an hour again. Like I said, this is important. Good luck!
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