I thought I would add to this thread instead of a new one. Most of my "third brake light" install is the same as the original poster. I'm only featuring my actual light(s).

I wanted a third brake light for safety, but I didn't want to change the appearance of the car and I didn't want any obstructions to visibility in my rear view mirror. This ment I needed a "low profile" light. Of course I wanted LED, so I searched the net and came up empty. If you can't find it, make it.

I did find this LED rope light at Superbrite LEDs. I also had some aluminum Z-angle leftover from another project. I believe I got this from Metal Depot online, but I think it's available at a hardware store.

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I cut and bent the Z-angle to give it a somewhat finished appearance. Painted it flat black to make it less noticeable. I attached the LED rope with aircraft safety wire.

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I attached the Z-angle to the louvers with some double sided tape. The lights/Z-angle don't weigh anything, so I hope they will stay put.

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From the side, you can't even see them. Also, they are completely invisible in the rear view.

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In broad daylight, they light up good.

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In the dark, I really like them.

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I was worried that maybe a tall truck behind me might not be able to see them because the louver would block it. But when I looked down at an angle, I found the lights reflect off the louvers.

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