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Which FMC Spark Plug #?

I have a 2008 F350 5.4l. It says 5/07MFG on the door sticker.
I wanna change the plugs and the boots. 120k miles on it now.

When I look up my vin# to check the OEM part I get 2 different plug numbers. 509 and 546.

I have the black boots if that helps. Just wanna know which plugs to get.
Also if I have the 2 part old 515 plugs which the 546 plugs replaced.

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