Dumb Question About Double Square Headlights

[Claus]

I have a set of the PMD Double Square Headlights, do you just epoxy the turn signal lenses on the end? Doesn't seem right to me but don't see another way. Also I assume the smooth side goes to the outside but this would mean the epoxy is really only holding on the high spots of the jeweled side. Nothing about this seems right to me, need help.