[Espeefan]

Lego light lenses can be flipped either way. If you use the lenses one way, the Lego logo shows, and is raised up slighty, but if you flip the lenses the other way, the Lego logo is mostly hidden, and the lenses are sunken in. Of course you'll still see the Lego logo, if you look hard enough, but it will be backwards, when viewed from behind. I think that's why you can't see the raised bump, which would attach to a Lego brick. He's got them inserted into the styrene backwards, techincally, or else he has them inserted the right way, but he only drilled the hole large enough to accept the little bump, and the rest of the lense is hidden behind the styrene.