This method require you understand and have adb set up. Works for both Mac and Windows. Also because I am a purest I prefer to do as much as I can via adb vs relying on a script or toolkit. So lets get started. Grab your tools from here: Nexus 6 root tools Android Forum at DroidForums.net Prep (this will wipe your device): Back up your data with your favorite back up app (aka TIBU) and move that folder to your desktop (computer) Back up your pictures and files (ie Dropbox, Drive, Google Music, etc.) Make sure you have all the files you need on your desktop (ie factory image and root tools (for those wanting to root...which by the way this works for both stock and rooted but stock can just flash the update.zip and not worry about this method). Steps: boot in to bootloader adb. Type cd (insert location of platform tools) <---hint it should be under sdk and in that platform tools folder should be adb, fastboot, factory image unzipped, twrp recovery, no encryption. The fastest way to do this (again you will wipe your device but this method ensures a clean install) is to do fastboot oem lock and the fastboot oem unlock. Once you click yes it will automatically wipe your device. Next we will go (mac: ./fastboot-all-.sh Windows flash-all.bat). In the event you have issues with the system.img file (which many did) proceed to step 4. If not Proceed to the step where we root and restore data. For those (like myself) stuck with a system.img error msg. follow this. ^for those during the "fastboot-all-.sh or flash-all.bat" who were able to get all flashed but the system.img then skip the first 5 steps and just start with step 6. After all is done we want to boot the device to ensure everything is all good. If so and you want to stay stock then you are done all you have to do is restore your device. But if you are following this most likely it is because you are rooted so let us continue to root and removing encryption...etc Go into setting in your device, enable developer options and turn on adb debugging (do not worry about setting up your device as you will be wiping it again anyway) in adb type: adb reboot bootloader Flash twrp recovery (for those wanting a custom recovery) : type fastboot flash recovery [recovery].img For those that want no forced encryption type: fastboot flash boot boot-501-noforceencrypt.img Using the volume key go into recovery mode and in twrp go to wipe and type yes as it will erase your entire device (which is already erased). If you are on at&t now would be a good time to remove your sim if you have not already as we will reboot the device. Use tap and go to restore your device will all your apps (should take about 5-10 mins) Go into settings and enable developer options and enable adb debugging. Connect your device and pull all your files (music, TIBU, su.zip, etc). After all your apps have downloaded and installed boot into recovery and flash the su.zip in twrp. Boot device and restore app data in TIBU. Now is the time you can reinstall your AT&T SIM ^This is a longer process but was a way I could make sure it was a clean install. Feel free to post alternate methods below.