i posted my adventures in that z4post thread, took mine apart and painted my silver backs matte black, also spray tinted my orange 'hockey sticks' as they call em to 'de-tango'
just used the set of lights that came with my car, cut them open using only one disk (the second one in your list for fibreglass reinforcing)
i decided not to add angels at this time, i like the look so maybe i'll cut em open again and add yellowish LEDs since i like that look better for daytime.
anyways, its pretty easy, glued em back shut with a no more nails type of construction adhesive, its light brown and looks bad but when they are re installed and hood closed, you dont see the seal.
I can answer any questions for people wanting to try this...