If you have the RDS static weapons addon it's really recommended to put the "UA_NI_vehicles" .pbo file from the "if YOU DO HAVE RDS_Static_Weapons addon" folder intothe addons folder, as it adds mobile ZU-23-2 gun and number of static guns to the UA Naval Infantry vehicles (which are APCs, static MG, trucks and jeeps in basic variant)

If you have the VTN mod and would like to have units armed with VTN weaponscopy the "UA_Naval_Infantry_units.pbo" from the "VTN_weapons_units" folder and past with replacement into the "addons" folder. This will change the armament of the UA Naval Infantry units to the weapons from the VTN addon