I've been contemplating this for years and years but never built up enough motivation to do it. I'm thinking about doing it more and more now. Since all the LED 3157 replacement bulbs just SUCK horribly, it seems to me the only way to make nice LED front & rear lights is to replace the bulb with one of those round LED lights you often see on trailers and big trucks.
I'm thinking maybe I could use the old Dremel and cut out the back of the taillight housing so something like that will fit in there. Same for the front parking light. Obviosuly this not a reverable mod, once you hack the light, thats about it. Then I would need to find a way to seal it and secure it in place since obviosuly it isn't a flat surface.