Most of the motion you are seeing in the video is the whole chassis moving on the supports I have it propped up on. The whole thing weighs about 100 pounds. Any flexing has the glue is flexing with the foam (between the layers), so that is a good thing. I will certainly test it. I still have to glue up the wheel skirts, so I can test on one of those, or make piece from the scrap that I have not thrown out yet...
The SuperBrightLED's site has some 5mm LED's that have built in resistors for 12v operation, and they have 3' long wire pigtails on each. The thing I am trying to find is a small round reflectors with flat lens.