
1: Download the RootS5.zip file and unzip it to your desktop.
2: Copy tr_v2.apk, BusyBox.apk, Safestrap-G900V-3.75-KitKat.apk and UPDATE-SuperSU-v2.40.zip to your extSd card on your phone.
3: Run Odin3 and load  G900V_NCG_Stock_Kernel.tar.md5 in the AP slot.
4: Shut your phone off and enter download mode by holding down the power, home and volume down buttons until it boots to download mode and then press the volume up key.
5: While in download mode connect your phone to your PC and Odin should say you are connected. Now press the start button to flash G900V_NCG_Stock_Kernel.tar.md5 to your phone. The phone will now reboot and update some apps, let it finish. After this there will be a bunch of force closes. Just close them until they go away.
6: Open your file browser, go to tour extSD, install and run tr_v2.apk, BusyBox.apk and then Safestrap-G900V-3.75-KitKat.apk in that order.
7: Shut down the phone, enter download mode again, flash NI2_stock_kernel.tar.md5 or whateverkernel is desired and reboot into safestrap. 
8: While in safestrap install UPDATE-SuperSU-v2.40.zip from your extSD card and reboot.
If all went well you should be on the NI2 firmware, rooted and safestrap installed. For those who do not want to install safestrap you can skip those steps and update superSU from the playsotre.