[LeEco Le 1S Guides, News, & Discussion] Gruffles01:
The steps that I used (and I hadn't messed with an android device for about 4 years so was feely quite rusty... but it turned out to be super easy... but a little time consuming):

A. Download twrp from here: http://www.mediafire.com/download/mcft20k2ib6e6v6/twrpLeTv1S.zip (but I used Ghost's twrp downloaded from here: http://www.needrom.com/download/twrp-2870-letv-x500-v2/). All you need to do is replace the recovery.img file in the first dowload with Ghost's (make sure it is renamed recovery.img if needed).

Then to install twrp:

1. Connect your phone to your computer via USB. Check in your PC device manager that the Android device is recognised. If not, download and install the drivers: http://www.mediafire.com/download/pk5pl58686a6bta/PdaNetA4183.exe

2. Enable USB debugging on your phone (if the option doesn't appear in the USB connection list then head to settings -> about phone -> and click the "version" info 8 times)

3. Run the file recovery.bat on your computer

4. Click Enter on your keyboard when prompted to press any key

5. The phone restarts into fastboot mode (black screen and tiny letters on the inside)

6. Now Press 2 on the keyboard and click ENTER to install twrp recovery

7. When it's finished then press ENTER again and the phone will restart in TWRP recovery

B. Root the phone - Flash SuperSU (http://download.chainfire.eu/743/SuperSU/BETA-SuperSU-v2.52.zip) through twrp. Don't unzip the file, just copy it straight to the root directory of the phone.

1. Reboot the phone into twrp recovery (turn it off and then hold down the power and volume up buttons together and it should boot into recovery)

2. select the install menu and install the supersu zip file (swipe to install).

3. Once installed your phone is rooted

C. Backup everything important - Download Titanium Backup and SMS Backup & Restore from the Play store

1. Use Titanium Backup to backup your apps, app settings and system settings (just the green coloured ones). I then copied the backup folder to my PC just in case but you shouldn't lose it on the phone during any of these steps

2. Use SMS Backup & Restore to backup your SMS/MMS (once again, I copied the backup file to the phone for security)

3. I use Google Photos as my gallery app so all my photos are archived into my Google account (and will restore once you install the app again) and I have all my contacts synched through my google account.

D. Flash 008s stock ROM through twrp (download the stock 008s from s7yler's needrom - http://www.needrom.com/download/letv-x5001s/)

1. rename the file to update.zip and copy it to phone's root directory

2. I had read that some people had an error message in regards to the update not installing as their phone was rooted so I removed root through the supersu settings

3. boot phone into twrp and install update.zip

4. The update removed twrp and replaced it with the stock recovery for me. I did a factory reset here to start fresh.

E. Update phone to 009s either through the phone's system update menu (which can take a while to download the firmware) or download 009s here (https://mega.nz/#!I5gSka4Z!zUzCHBTZEg_SxP-29ctPST6tEu4g38Xj34FkjUXnf-c) and rename it to update.zip and copy it to the phone (replace the file from step D). You can then go to the system update settings menu and select "local update".

- I did a factory reset here again just because I felt like it.

- Once setup I deleted any Chinese apps I could

F. Reinstall twrp using the instructions in step A

G. Reroot using the instructions in step B

H. OPTIONAL - Reinstate the 900mhz band using the first procedure listed here: http://xdaforums.com/showpost.php?p=64791418&postcount=91 (this involves another factory reset)

I. Install Gapps through google installer using the instructions here: https://www.youtube.com/watch?v=q8ZidFOzl-k (the link to the google installer apk is in the video description or use Adex2014's link - http://xdaforums.com/showpost.php?p=64965380&postcount=126). You might need to wait a little while after installing Google play for it to update to the latest version, otherwise most apps will say they can't be installed. If you see this message, just close the play store and wait some more.

J. Restore your data - install Titanium Backup and SMS Backup & Restore.

1. Restore your apps, app data, and system settings through Titanium Backup (this took a while as you need to manually accept each app install)

2. Restore your SMS/MMS through SMS Backup & Restore.

3. If you use the google apps like I do then your pics and contacts should be restored after you login to your account and install Google Photos.

K. You might need to change some other settings back like notification management and smart battery lock for apps.

L. I left my phone with twrp and root so I won't get OTA updates, but will just install them manually. If you want OTA updates:

1. unroot your phone through supersu's settings menu

2. install stock recovery using the instructions and files on s7yler's needrom page (http://www.needrom.com/download/letv-x5001s/)

*phew* That should do it. These steps are taken from a whole bunch of different sources so thanks to a whole heap of people (e.g. ghost45, s7yler, qualin and Adex2014)