Early FIY for your DIY...
Look up P/N 7027-D-350 on DigiKey to get your 350mA driver, and drive it with a high current LED of your choice.
I'm a Luxeon guy, but they've since switched over to the Rebels (small surface mount). The Rebels are a bit more delicate, but the brightness is pretty amazing. Each of my reverse lights has a Tri-Rebel star, and it's way brighter than my gf's daytime running light.
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