I'm using Twisted V7 from here
http://xdaforums.com/tmobile-galaxy-s5/development/rom-twi5ted-lollipop-5-0-v1-deviant-t3037766
Download and save it to your SD card.
Then go here and download the OC4 Retail Firmware Only file
http://xdaforums.com/showthread.php?t=2784880
Save it to your desktop.
Boot to SafeStrap or Flashfire and do a wipe for clean install. Then install the downloaded rom like normal.
After it installs re-boot directly to Download Mode (if using FlashFire you need to select this before you flash or you'll have to do it manually after an unsuccessful boot)
Open Odin and click AP. Browse for the OC4 Retail Firmware Only file you saved and click start.
After a few seconds the process will complete and your phone will re-boot at that point you are done and can unplug from the computer.
Give the phone a few minutes to boot. Mine took about 5 minutes. That's it.