I have added this thread to the Root Guide sticky.
Just something everyone should note, if you are wanting to accept OTA updates installing this radio may prevent you from doing so.
If you wish to flash back to the prior radio(s) and/or bootloader do the following.
1. Download this file
it is the factory image from google and can be found here
verify the MD5sum is bafc4d3c5faa9822f76a5313fc91f743
2. Extract the file and move the radio(s) img files to the same folder your adb.exe and fastboot.exe files are in.
3. With the phone powered on and with USB debugging on plug it into the computer.
4. Hold shift and right click on the folder you placed the img files in. Choose "Open command prompt here"
5. Execute the following commands in the command prompt:
adb reboot bootloader
fastboot flash radio radio-toro-i515.ek02.img
fastboot flash radio-cdma radio-cdma-toro-i515.ek05.img
6. Reboot your phone by highlighting “Start” and pressing the lock switch and you have restored to the previous radios.
Note: If you wish to only revert 1 radio then leave out the fastboot commands for the other radio. If you are wanting to play it safe and revert the bootloader too then run these commands as well (also move the img file to the folder with the radios)
fastboot flash bootloader bootloader-toro-primekk15.img