I've got fiberglass inserts and a Kayline top/doors. Since I've owned the scout, there's been a gap in the area up front where the insert meets the window frame. There's also been a huge gap between the tailgate and the lower lip of the rear window (snap style). Not sure if this was a PO installation issue or not, but it's not good. At speed, the door gap draws a lot of air. Air coming around the side of the windshield creates a big vacuum just outside the door. This, plus rear window gap leads to major exhaust infiltration. I rarely have the top on, but it's nice to be able to take a trip in the winter and stay warm AND alive while doing so. Anyway, this weekend I decided to do something about it. I fabbed some simple metal plates (16 gauge) mounted between the aluminum angle and door insert to cover the gap and improve the snap mounts. I also added some weatherstripping here and on the top lip of the tailgate to seal off the air. Turned out great.