Use the restore images to return your new Nexus 7 to a factory state
The factory restore images of Android 4.3 for the new 2013 Nexus 7 have been posted up at Google, allowing folks a path of safe return if they decide to modify the firmware on their device. The images contain a complete backup of the "stock" Android system, and are easily flashed using a computer.
Some hullabaloo has been made, with folks saying we might not ever see these, or starting petitions against parts vendors. It would seem a little patience would have been a wiser choice.
In any event, if you have a new Nexus 7 and like to tinker, grab them at the link below.
Source: Google. Thanks, Kyle!