Hey guys, I saw on here that a lot people seemed to have questions about the GS300 after market radio installation. So I just put a radio in my wife's car and thought I'd take some pictures during the install that might help you guys out. I was an Assistant Car Stereo sales and installation manager at Circuit City for 3 years so I have a lot of experience doing installs. So here we go:
I started by making a harness that was about 36 inches long to reach from behind the radio to the factory amplifier:
I left a quick disconnect harness on, like the ones at circuit city, incase I change out the radio later, this way I won't have to wire anything else up.
Next I dropped the glove box and located the factory amp and the output wires from the factory amp (an met 80 or 70 1761 from BB or CC will fit this harness).
Here's a close up of the harness and where it was unplugged from:
Factory Amp location on right:
Next I got 12 volt switched (accesory) from the harness behind the factory radio (not the factory amp) it is a gray wire:
Now I decided I wanted to try and keep the factory sub-woofer. To do this I wired in the sub-woofer wires (green w/red & green w/black on the small harness coming off the factory amp) to the driver's side rear speaker. The downside to this is that the factory sub and rear driver's side speaker are lowered to 2 ohms. It did not sound like any highs were getting through but it is difficult to tell since I can't fade the driver's rear off or it gets no signal. Here is a picture of the wires off the factory harness with the wires jumped from the driver's side rear speaker spliced and soldered on:
Next I grounded the radio to the gold colored bracket to the right of the glove box:
Here's a close up:
Last, I ran the wires along the same path as the factor wires and zip tied them in place:
And that was it. I soldered everything and I would recommend that you do the same. Time will tell if leaving the factory sub hooked up is a bad idea or not, but it definitely needed some bass when disconnected from the factory amp.