Hello all, I got stuck in today with doing this, it looks better than the 2 LED trick, but costs more. I got the screen from the store I do repairs for, it came from a dead DS, where someone had stabbed the screen and it also had a dead board. For the 12v supply I used a LM2577 pre-fabbed board I got from ebay for about $6 or $7AU.
First pic is of DS lite Backlight, the screen here has been removed
I replaced all the caps to get it going 100%
The usual LED mod parts removed, having a de-solder gun is the key