The white LED has a yellow phosphorus The amber LED appears white when off so it dosent look like that,but man these jokers are bright.
The hidden halo will be behind the e46 shroud, with the little slits pre formed in the shroud drilled out to allow light through. awaits to see another variation of this idea like before lol
Do a quick google search you will see tons of people who have done that, it looks great with the amber IMO.