I just finished installing this exact set of lights in a friend's wing. I did not notice any half inch gap. Might be a quarter in at most. No the light are not white. They actually have a very light hint of blue. Sort of like the blue/white auto bulbs. Over the years some folks have had problems with this style of power delivery system. I've got almost 170,000 on my fog lamps and have not had a problem. The bypass plug will not supply more power. All is does is eliminate the relay so you have to turn the lights on and off with the switch.
Hope that answers your questions....