i'm running 6.5" kenwoods up in the front. i need to replace the rears. i tried out the 4"x6" pioneers a while back and it was too overpowering. meaning, i felt it was actually overtaking the acoustics of the front speakers. so any advice on a modest set of rears? by the way, i lost the bose rear speaker enclosure. would it be a problem to mount the speakers without using them? thanks.