I struggled with the plastic trim pieces too, and tried everything to get them off including slipping dental floss into the thin slots to loosen them up. Fearing I would eventually break the fragile plastic, I just CAREFULLY pried the lenses off (making sure the rubber gaskets aren't damaged), which works just fine. Not removing the plastic trim just means spending a little bit more time when putting the lenses back onto the housing. It's easiest to push the bottoms in first, making sure the rubber gaskets are firmly seated in the grove/slot made by those plastic trim pieces. As I mentioned in my original response, a bit of silicon on the rubber gaskets will help with reinsertion of the lenses and gaskets, as well as preventing moisture seepage (sp?). Also, it's crucial that the six metal clamps are seated properly on the lense lips, which requires applying some pressure on the lenses and slipping these clamps between the plastic trim pieces and lenses. This was the best solution for me, considering the alternative of breaking the plastic trim pieces and having to replace them. I've taken off the lenses twice already and have had success both times following this procedure. Let me know if you have better solutions.