You have the wires correct. Here is your confirmation, plus the pin locations on the main radio plug.

Pin 2 Blue with Red Stripe: Right Front +
Pin 3 Yellow with Red Stripe: Left Front +
Pin 6 Brown with Orange Stripe: Right Front -
Pin 7 Brown with Orange Stripe: Left Front -

However, you will probably run into another problem. When the radio senses a DSP amp in the car, it changes its behavior from what a normal car radio does. It feeds full volume, line level signals to the amp. All of the volume, balance, and fader level adjustments occur within the DSP amp and not the radio. So, anything you connect to those audio feeds will blast at full volume.

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