I own a 2007 Chevy Cobalt LT Sedan. I want to know if it is possible to install the pioneer subwoofer that comes with some of the Cobalts' with Premium Sound; my Cobalt, however, does not have premium sound. I do not want to install and amp or and after market stereo. I simply want to know if the wiring harness has the connections. The car has the mounts for it....