How to overwrite sqf file from campaign pbo?

[pcc 14]

File trying to edit is at

file="\a3\missions_f_epa\Campaign_shared\Hubs\initFF.sqf";

I'm trying to using cfgpatches to remove friendly fire handlers from the campaign pbo, but I'm not sure what's next after this

class CfgPatches
{
 	class missionEdit
 	{
 		units[] = {};
 		weapons[] = {};
 		requiredVersion = 0.1;
 		requiredAddons[] = {"A3_missions_f_epa"};
 	};
};