On a stock factory V9 ROM, there usually is no install-recovery.shflash_image & recovery-RA-GNM-thunderc-s-1.1.0.img extracted & on SD
all steps worked fine until this:
# mv /system/etc/install-recovery.sh /system/etc/install-recovery.sh.bak
...and get this....
failed on 'mv /system/etc/install-recovery.sh /system/etc/install-recovery.sh.bak' - No such file or directory exists
I'm guessing the install-recovery.sh is missing?
As part of the OTA update process, if they need to update the Recovery partition, it is done through that script, and left behind.
If you don't move it out of the way, it could give you troubles when you try to install your own Custom Recovery partition.
However, as mentioned above, you may or may not have that file.