Got mine at radioshack too, it's a 60 watt. Mine is directly behind the grille in front of the radiator. I painted it black so you can't see it hardly. This is an old pic, but you can see the pa speaker on the right side behind the grille. If you get one, mount it here, if you mount it under the hood it will sound muffled and not near as loud as how i have mine mounted.