This is a photo of the 3rd brake light I added to my '66 Coupe. Sorry for the dirty window. It came from an '89 Mercury Marquis. I have an aftermarket wiring harness so it already had wiring to the trunk for it. I grounded 1 side and spliced the other on the new harness. Bought LED bulbs for it. I thought it blended in OK. I just like the idea of being as visible as possible. (Can also see the top of a 2000 fold-down seat too. It sticks up a little, but not too bad. It is however, not really wide enough)