I went with an affordable Kenwood KDC152 receiver, 3 way kenwood 6x9s in the rear package tray, and 4" 3 way kenwood speakers for the dash. I still have to decide where to mount the receiver, glove compartment seems awkward to me, even though it has a remote.

If this setup isn't quite enough I might add some 3 way 6" round kenwoods in the plastic kick panels by branching off the dash speaker wires, would that cause any problems?