The "gap" you're referring to?? Is it the slight potential air space between the stongard film covers and the hard plastic of the headlights?
Would heating the stongard covers with a hair dryer be a good install tip? Any other tips?
Any other type of UV inhibitor that can be applied to the headlights or to our stongard film covers? Anything like a consumer spray-on UV?
I'd asked the ebay seller of our Stongard covers about UV protection. He didn't "think" they had any. Maybe we could drill down a bit further with the manufacturer about it?