[HELP PLEASE] Which recovery should I use on OC3 (I337) bootloader?

I'm just curious of bricking my phone.
Which recovery can I use on my i337 OC3 stock rom. Its not rooted (I tried King root desktop version but didnt worked for me).
I read somewhere that safestrap is not compatible with OC3.

Straight-forward way to root i337 Android 5.0.1

I've been searching for a way to root my SGH i337 phone on Android 5.0.1.
I found threads that say to "Downgrade" or "Flash NB1". Then i went searching on how to do either of those things and all i get is downloads to dead links.
Nothing straight-forward that is actually going to help me root my phone. I haven't been able to find a simple guide on doing this could someone point me in the right direction? I'm ****ing frustrated.

[Q] Need serious help to safely restore i337 to stock everything

I received a new phone since I broke my old GS4 (I337). It was on AT&T 4.2.2 and I rooted it using motochopper. It was fine. It automatically updated while I was asleep to 4.4.2. I had rooted my old GS4 on the same update. So I figured I'll just root it again. So I used the method where I flash the NC1 kernel, use towel root, then flash NJ4 back. Now my WiFi will not turn on, but I do have root access. Also, a message saying "Unauthorized actions have been detected" and it tells me to restart to undo these changes. I don't want to do it in fear of bricking my device. I'm really scared now and I desperately need to fix this. I just want to go back to complete stock 4.4.2. I've tried reflashing the NJ4 file twice and WiFi will still not turn on. I've attached pictures of the notice and my device info. Please help. I cannot brick this device. I will answer to any questions as fast as possible. At the moment, I am debating whether or not to flash this because I am unsure if it will be compatible. ALL_ATT_I337UCUFNB1_I337ATTFNB1_505595_REV06_user_ low_ship_MULTI_CERT.tar
http ://i.imgur.com/68B7MNM. png?1
http ://i.imgur.com/6Cjnzug. png?1

i337 NB1 impossible to install custom recovery

well i kno i have a looked bootloader but even with loki or safestrap i was able to install a rom, a really hate original rom so i want something else.... its there a way to have a recovery working on this baseband'?

i337 MF3

I have a motherboard clean EMEI bootloader MF3 (very rare, only bootloader version you can loki to install any i9505G rom and keep LTE for AT&T)
Current ROM official 5.0.1 Google Play Edition

anyone interested ?