First you need root.. Of course.. But once you've got root.. are we doomed to stock? Nope. Go to playstore and grab 'Rom Installer'.. link... https://play.google.com/store/apps/details?id=com.jrummy.apps.rom.installer
Open the app and if your running the old 720 you can skipe this step and move to step #2.
Step #1.(L720t only) open rom installer app.
Go to setting of app.
and choose user defined device.
Change name from 'jflterefreshspr' to 'jfltespr'
Step #2. Select a custom Recovery such as TWRP/CWM..
Step #3. After flashing (I CAN'T PRESS YOU ENOUGH TO STOP HERE AND MAKE A BACKUP OF ALL PARTITIONS IN RECOVERY!) . Reopen app.. and select ROM of choice..
Step #4. Reboot, wipe cache and whatnot...and flash. All is automated at this point. After it finishes downloading.. it should ask if you want to flash. Hit yes. Done.
Open the app and if your running the old 720 you can skipe this step and move to step #2.
Step #1.(L720t only) open rom installer app.
Go to setting of app.
and choose user defined device.
Change name from 'jflterefreshspr' to 'jfltespr'
Step #2. Select a custom Recovery such as TWRP/CWM..
Step #3. After flashing (I CAN'T PRESS YOU ENOUGH TO STOP HERE AND MAKE A BACKUP OF ALL PARTITIONS IN RECOVERY!) . Reopen app.. and select ROM of choice..
Step #4. Reboot, wipe cache and whatnot...and flash. All is automated at this point. After it finishes downloading.. it should ask if you want to flash. Hit yes. Done.