Would help if we knew something about the "application" your wanting.Ever been here?
http://www.superbrightleds.com/cgi-b...Fled_prods.htm

The idea is to create LED lighting for the car, in a manner that can not be done with an LED replacement bulb in the stock reflector. I want uniform coverage, and increased visibility, striking a balance between safety and aesthetics. Most of what I will likely be doing will involve building my own lights using LED bulbs and wafer boards, and LED strips when I can get away with it. I also plan on putting in DRL'*, in a manner that can only be done with the Buick front end.

I do not think you can increase visibility that much over stock lighting to make your project worth the time and effort.

However if you are going to illumniate a reflector that is a different ball game and a neat mod.

Putting lights in places that do not have lights is also nice mods.

I wish I had an extra set of tail lights to play with
I'd love to take the GXP tails apart and see what I can do for an LED project
More like add led strips on the reflectors, this way they are bright for sure... I dunno I know I'm crazy but just an idea

It has been done and you are not crazy.

was it on this forum?
any pics?

Dug in the basement and found:

Here

https://www.gmforum.com/showthread.p...LED+headlights

Here

https://www.gmforum.com/electrical-133/00-center-tail-light-up-write-up-287275/

Here

https://www.gmforum.com/showthread.p...&highlight=LED

i got them in today, they are bright *****

How bright in comparison to something recognizable? How much heat do they put out?

brightest LEDs ive personally seen (ive seen ALOT of LEDs believe me lol)
they do heat sync gets very hot in less than 5 minutes, kinda odd for LEDs