Have the bose system in a 04 touring with nav. Trying to keep the stock look so going to keep the head unit for a while. Was going to get a 4 channel amp with new kappa's mids and tweets up front. going to keep the crappy rears in for a while.Will running 2 channels up front and 2 to the sub mess with the h/u. any recommendations on a good priced 4 channel amp?. Also need some help removing the acutal stock sub after removal of the rear plastic. thanks in advance