Front fenders aren't too bad to get off, depending on rust. A few bolts under the hood, screws for the fender liner, a couple of bolts at the lower rear of the fender, and 2 bolts, I think, from the bottom at the front of the fender.
You have to do most of the work of removing the bed just to change the side panel. Swapping the entire bed would probably cost more, but be a whole lot easier. 4 bolts in the bed, some small screws to separate the gas filler hose, and some wiring. If you swap beds, be sure to check the steel under-structure for rust. About all you can really see is around the tailgate opening and hinge.
I spent much of my long July 4th weekend swapping the bed and rear bumper on my '01 Sport Trac. Anyone thinking of doing this job should not be scared off by the amount of time it took me to complete it. The actual bed swap went smoothly, and could be accomplished by 2 people in 1 to 1 1/2 hrs...
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