Dumb question, how do you know if you have a factory installed amp. in your car I have the bose cd plus the 2door, 2 rear and a single speaker in hatch how do you tell where would the amp be??? I went to Best Buy and they said I have it I went to Circuit City and they said I didnt. I didnt have the car there at the time due to its cold and crappy outside. I need to know how do you find out.