Will these steps brick my phone???
1. First you will need to backup your LG Optimus V's current OS. Go to the Android Play Store (Market) and download ROM Manager.
2. In ROM Manager, select "Flash ClockworkMod Recovery" and wait for it to finish.
3. In ROM Manager, select "Backup Current ROM" and wait for it to finish.
4. Go here and download signed_ICSandwich v3.zip.
5. Put signed_ICSandwich v3.zip on your LG Optimus V's SD card.
6. Reboot in to recovery mode by pressing the volume down, home, and power buttons on the LG Optimus V all at the same time.
7. Select "install zip from sdcard" by using the volume buttons to navigate and the camera button to accept. Next, select signed_ICSandwich v3.zip on your SD card. Select "yes" when prompted and wait for the installation to finish.
8. When it finishes select "reboot system now". Once the system reboots you should now have Android Ice Cream Sandwich on your LG Optimus V. Congrats!
9. If anything goes wrong, reboot in to recovery mode and select "backup and restore". Next select "Restore". The date of your backup should come up next. Select it and allow the backup to finish, then reboot your phone.