Hi Patrick,
Could it be possible that some former owner unintentionally bent the U-shape clip, (Bratton's #17910) at the bottom of the headlight buckets which secure the Rim Latch Post Set T-bars, (Bratton's #18020/18050).
Also, with vibration, the neoprene gaskets, (Bratton's 18130), appear to bounce back to original thickness after the head light rims are removed.
One dab of clear silicone sealant at neoprene joint, and one dab at top & bottom works well to keep gasket in place before headlight rim assembly.