The stock android launchers are very inflexable, pretty much the only thing that's adjustable at all are the size of widgets in 3.2+. Anything else is pretty much what it looks like and not changable.
If it's important enough you're gonna need to use a different launcher like launcherpro previously mentioned.
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Nexus 4: Stock JWR66Y (4.3) 2013 N7: Stock JSS15R (4.3)
Touchpad: CM10.2 JLS36I (4.3.1) iTouch 5G: Stock 10B146 (6.1.2)