Actually, it's probably easier to get two pair of 3D glasses and then swap the left eye of one with the right eye of the other. No trimming needed. (Edit: come

Actually, it's probably easier to get two pair of 3D glasses and then swap the left eye of one with the right eye of the other. No trimming needed. (Edit: come to think of it, there may be some trimming needed if the left and right glasses aren't the same shape but in that case flipping them over would probably work unless they are curved)