I would definitely be installing these myself. I am a mechanic, so I get the side benefit of saving myself a boat-load of money on my automobile obsession. I am keeping this truck until forever. These Expeditions are fairly cheap to repair compared to some of the other trucks out there, especially the imports.
About the headers, if I can find out that the ones that I'm looking at do indeed fit then I am going to get them. I want to do a full exhaust upgrade on this truck. Headers, high-flow cats, cat-back system. I will also be getting a programmer in the future, as well as an electric fan kit from Troyer. I want to maximize power and efficiency on this thing.
My concern with the headers fitting isn't so much the bolt pattern for the exhaust manifold on the 2V heads I have. It's whether or not there was a change in the shape and/or contour of the Frame of the truck from the old body style to the new on the passenger side. One thing Gibson told me was that the passenger side header for the part number that I referenced was the only difference between the GP220's and the GP206's. But, I have one guy (Gibson employee) telling me that they're for the 2V (he thinks), and another Gibson employee telling me they're for the 4V (he thinks), lol. Soooo therein lies my mystery.
Edit: The 4V engine I reference is a Navigator only option BTW (I guess
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