It's pretty random. I can usually get it between some combination of CTRL+SHIFT+[ with some parts and CTRL+SHIFT+] with others. I think part of it may have to do with putting the breadboard itself in the very back and then locking it. I know I've done that, but I don't know if that was a key to making it work or not.
Here's a quick video of me doing the trick. http://www.youtube.com/watch?v=iVCV9WowBcs
The first time before recording the video, what I did was to select each LED and then DELETE followed by CTRL+Z. That didn't work. So I just tried DELETE and CTRL+Z again. Still didn't work. Then, with all the LEDs select, I did CTRL+SHIFT+], then DELETE, then CTRL+Z. And that worked.
But when I recorded this video, that pattern didn't work, but some other pattern did. So there is no absolute sequence that I can figure out that works every time.
Which LED? I know I can reduce the size of the LED to 3mm, and I've seen some other LED that appears flat ... and that would be great ... but the one I'm thinking of takes up a 3x3 area (which is too big), and it isn't the right size for going between a row and a power rail.
