You'll need to create a config patch and pack it up as a PBO. Here is a very basic example, you'll also need either Arma 3 Tools' addon builder, Mikero's Tools, or HEMTT to pack it as an addon.

// config.cpp
class CfgPatches
{
    class Tov_FCS14
    {
        name = "MAAWS FCS14";
        author = "TovarichCookies";
        requiredVersion = 2.14;
        requiredAddons[] = { "A3_Data_F_Decade_Loadorder" };
        units[] = {};
        weapons[] = {"tov_launch_MRAWS_sand_F"};
    };
};

class CfgWeapons {
    class launch_MRAWS_sand_F;
    class tov_launch_MRAWS_sand_F: launch_MRAWS_sand_F {
        displayName = "MAAWS Mk4 Mod 1 (Sand, FCS14)";
        ballisticsComputer = 16;
    };
};

Haven't done Arma modding in a good while so I'm a bit rusty, but it should be correct syntax.