I think that's because on some models the last bow goes all the way down to just above the rear seat. My 2 door post happens to be one of those. Haven't installed mine yet (hopefully in the next month or so) so I can't comment on whether or not it works to stay in the listing channel all the way down or it has to be cut and run down outside the channel behind the headliner. It's either that or it's just easier to run the channel longer than needed to be "trimmed to length"
