the color chnaging is based on the same premise that the multi colored indiglo gauges are. You press a button and it switches the color for you.
These are not hard to make at all. I have a set made for my highs that I cant put in for another week or so and I am making a set of angel eyes for the fogs which I hope to have in by the end of this weekend.
Like has been said the hardest part is taking the headlight housing apart. Alot of people have almost screwed theirs up buy using an oven.
I use an electric heat gun which you can control how quickly it is heating up and you can pry while heating.
Ill get some pictures doen in about 2 weeks when everything is done, I am painting the upper grill bar body colored, the black headlights, angel eyes, some city lights I might install, clear side markers and I might redo the upper grill to remove the M.
should look nice when its all done.
BTW the supplies for the angel eyes:
acrylic rods from home depot(doesnt have to be smooth round, long as you do it right)
LED (2for ea ring) from radioshack
resistor, around 2200ohm is fine, radioshack
a butter knife or even better a dremel
oven or heat gun
thats it basically, there is a how to on this I can go find if others are interested.