The bright ones at the end are the square LED's, they are a little more expensive then the regular ones but they put out a broader range of light. They come with 4 prongs on the under side, I just bent the prongs down and hot glued them to the disc. if you use champion plastic it wont damage the plastic when you pull them off.
Similar, I made a couple modifications. I trimmed the Led & bent them to hug the battery & added detailed visual instructions. I think I am going to try & focus on the square ones though. They are much easier to see from far away.