Hi Bill,
The back up lights are more to warn the people behind you that you are backing up. Stock backup lights suck if you needed them for illumination. At least the ones on my 69 are.
The stock license plate lamp housing that sits in the bumper can be modified to house a full row of LEDS, I plan on having 2 to shine down on the plate then 4 to be aimed rearward. Something that would be very visible.
Its not necessarily flush but hidden. You can even put a nice row under the corner of the bumper if illumination is your goal.
Shoot me an Email and I can send you a few resources.
Vince
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