I'm not too sure about what you're requesting. Just blacking them out wouldn't work. You'd still have the grey that is visible when you lose signal strength, bars, etc. The only ROM (that I know of) that has the ability to actually hide the signal (data) bars is AOKP. But note, there is a blank space where the signal bars are supposed to be when they are hidden. If I could, I'd pull the source code from AOKP, take a look, and make a flashable zip file of a mod for you. But I cannot, for I'm no developer. I'm pretty sure someone on this forum would be willing to help you, you might not be the only one who wants this.
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