How to attach shrouds to projectors?

Most retrofitters including professional shops use either JB weld epoxy or clear silicone glue to permanently affix the shrouds to their projectors. Both do well at resisting heat, but the silicone stays flexible, will not crack over time from vibrations etc like JB weld might. Clear silicone can however release vapors or moisture when heated, so it should be fully cured before resealing the headlight housings.