The parts have been virtually unseen in the last 5-10 years, it's very hard to guess what they would sell for now. The bumpers and wing used to be a close to $500 item, but the last I saw were near $250, that was almost five years back. The wheels are likely not authentic, the originals were recalled, they were magnesium and not strong enough for street use supposedly. I've read of two original sets of wheels, one member here found them low and put them on his white Limited.
That truck unfortunately doesn't have many of the XP8 parts, about half of them. The CF hood, steering wheel, mirror covers, front bumper of course, CF interior trim pieces, and supercharger are not in that one. I think I saw the pedal covers there. There were cocoa floor mats that most XP8'd had, but those were fragile and worn out if you find those.
That truck is probably only worth $1500 without the Saleen parts, guessing the chassis is rusty at the least. I have the pieces I wanted the most, but wouldn't mind finding the side pieces or a better rear bumper. The other parts would not bring enough, the truck selling price would make the deal expensive. You don't want to pay $3000+ for the parts in the end. Here's a picture I have of most of the main parts, a member 12 or so years ago sold it off then. I got the front bumper, and below is a picture showing the optional Recaro seats, those were super high, not many existed.