This modification disables map specific and game specific weapon limits.
There are a couple of versions I made so you can pick which one fits best.
Compile one of the files as _zm_magicbox.gsc and place it in \t6r\data\maps\mp\zombies.
Disables the check for already having a weapon that is in the box.
This means you can get the Ray Gun out of the box when you already have it, doing so will refill its ammo.
Having the PAP'ed version of a weapon counts as another weapon, so you can have the Ray Gun & the PAP'ed Ray Gun.
Only disables weapon checks for wonder weapons, so everyone can have a Blundergat and it is not capped to 1 per game.
This also means you can have a Ray Gun & Ray Gun MK2 at the same time.
Combines the 2 tweaks listed above. (Recommended)
Disables all box checks, this means non box weapons (such as some wall weapons) will be placed in the box. (Not recommended)
This repository from JezuzLizard with compilable GSC files. https://github.com/JezuzLizard/Recompilable-gscs-for-BO2-zombies-and-multiplayer