Not sure if this is the correct thread to attach to but all this discussion about LED lights has brought a thought to mind.
There has been concern about the visibility of our low cars and I was wondering whether this could be offset a little by attaching rear cycle lights to the top corners of the luggage rack for temporary night time use. Cycle lights are now bright, reliable and long lasting.
I can't find anything in the highway code other than that one shouldn't keep a brake pedal depressed when stationary in traffic although there must surely be some legal guidance, and indeed restrictions, elsewhere as to positioning and use of such devices The advantage of a cycle light to me is that it would be easily removable when parked up.
Just a thought and may turn out to be a silly one.