Ok, I managed to do it using these steps:
1.Install stock firmware(4.2.2)
2. Using cf-autoroot, root your device http://forum.xda-developers.com/show....php?t=2219803
3. After your device is rooted install triangle away https://play.google.com/store/apps/d...ngleaway&hl=en
4. Read all of the instructions carefully and reset your status and flash count.
5. When the triangle away bootloader thing asks you to either reboot or reboot to bootloader select reboot.
6. Now factory reset your phone again from the accounts menu in the settings.
7. After that has finished you should have an official status and be able to recieve OTA's.
NOTE: When I did this process I still managed to keep the phone rooted.
This was testing on an i9505, have no idea whether this is working on other models.