These things are pretty freckin' sweet. I'd totally rock a set if I had one. Take note GR owners $200 or so from Japan Parts. I realize that's a bit steep, but you wont get the function and form from a DIY, IMO.
Not LED, or at least multiple LED, probably just a single LED, but they looked damn good. Especially with the Painted Tail lights to match. Face's GR is the way it should have come from the factory. Not the best angle in the pic here:
It wouldn't be difficult to do a great DIY for this part. The question is...is $200.00 enough bones to make you do the DIY, get a board, solder some LEDs and make it work? If you like doing this kind of thing, it's a great excuse to draw up a small board layout and go to town