Jenn D is correct. The 2004 bumper covers are a noticably darker shade of grey, more like a charcole color. They will fit and bolt right on, but the bumper color will not match you existing side cladding.
Also, early model Sport Trac's used light grey treads on the step bars and rear bumper that matched the cladding. In the middle of 2002 they switched to black treads. It's possible to remove the treads from your truck and move them over to the new bumpers, etc however the holding clips are prone to break off while attempting to remove them.
...Rich