To the OP (and others), just as an FYI, from the looks of it you wired your speakers with the reverse polarity. Those Metra harnesses (72-5600) are wired the exact opposite way that they're supposed to be. I would recommend picking up a set of adapters from Crutchfield instead. They're basically the same price, but the difference is that your speakers will be in phase and you'll have more mids/lows (within limits of what the stock amp can support). For reference, this is the difference between the Metra adapters and the Crutchfield adapters. Please excuse the typo within the picture
I originally bought the Metra adapters (72-5600), but when I changed them out for Crutchfield's, the sound difference was huge.