Install direct downloaded IOS 6.0.1
iOS Updates Using a Downloaded IPSW File

Note that .ipsw files are specific to the device (i.e. the iPhone 4 GSM is distinct from the iPhone 4 CDMA). Make sure you download the correct one.


Plug your iPhone into your computer with the USB cable (Wi-Fi won't work for this).
Open the iPhone device page in iTunes (either from the sidebar in iTunes 10, or the Devices button in iTunes 11).
While holding down option (or shift in Windows), click the Restore button. You should get an open file dialog.
Select the .ipsw file you downloaded, and click OK. Your iPhone should start to update normally.