I'm just going to run the 4 6.5"s which are already installed.

Alpine SPS-1629S 6-1/2" 2-way Speaker at Crutchfield.com


My main concern is the factory amps are made for the 2-ohm factory speakers and aftermarket ones are 4-ohm. I've heard anecdotal evidence both ways in regards to the sound quality of aftermarket speakers with the factory amps which is why I was interested in finding out their actual power output.