My sliding canopy doesn't move as cleanly as I'd like. The problem is that before the canopy is installed on the plane, the span of the rollers is about 1/4 in wider than the tracks on the fuselage. This means that once installed, the rollers are braced against the outside of the tracks. I'm considering adding a second roller to run along the outside of the track to keep the primary roller centered but thought to tap the experience of others before making modifications.