This worked!
I also removed it from the base progression.xml file as well as the one in the save folder. Without removing it from the base file, the game kept reloading it into my save.
Thanks for the help!
So I completed the Shotgun Messiah book collection, and unlocked the bulk shotgun ammo crafting and the horrible perk that allows a shotgun blast to destroy wood blocks. I worked hard to get to where I could run and gun with my auto shotgun, but just destroyed half a POI killing zombies because...