The biggest difference between the '98-'05 and '06 and newer tps will be the side marker light assemblies. bdp's tour pak is the '98-'05 version based on the pics from an earlier thread he started (side marker lights don't wrap around the rear of the tp, nuts for the metal plate in the bottom are not recessed in the bottom of the tour pak, etc.)

My original birch white tour pak was the pre-'06 version. With the exception of the rivets for the hinges and lid latch, everything was assembled with screws/nuts and the wedge devices used to secure the rear light bar.