Adding siren to unit, doesn't work?

[KayEffAre]

Alright, so I'm attempting to add a unit from a friend's unofficial LA Mod update (already has the LA autosiren script) into my regular LA Mod game. I folllowed the tutorial listed here, but when I toggle the sirens, there's no sound? It should be pointed to the police siren file, but I can't seem to find it? Where should it be? And if I need to, what code should I be adding to point to the police siren file?

[FInn Rescue 12]

Try open the EM4 folder of the mod you change the siren.  R click the EM4 look for the mod click on the mod  look for Audio file click on the that. Then look for FX file next click on that and look for the siren file open it and check for the siren.  Or if it is a newer unit you would have to add it the siren script for it to work.