ok on my 05 it has a hard plastic "junction box" so to speak before going through the rubber flex point the 04-05 also does not have "Explorer" badged on the side, the interior panels are definitely different the older ones have circle grills for the speakers and silver grip handles that fade and wear the newer ones like mine are a rectangular grill for the speaker and molded black grip handle. the swiches for the windows are back lit and straight (parallel to the door) similar to the switches in the third gen sploders not sure if the switches are slanted or not in the 01-03
those are some of the difference i can mention. just like the 01 trac having headlight switches recessed into the dash wereas the 05 has a third gen style where the headlight and dimmer is in one unit that snaps into the dash. like the superduty's too