using factory speaker outputs

Hey Guys This Is my first post and i just have a simple question, i was wondering if it is possible for me to use the factory speaker wiring coming off the radio harness to connect my speaker wire leads coming off my external 4 channel amp, i think it should work but i just wanted a second opinion on it. thanks

Just to so you guys have a clear image of what i mean

What vehicle? Does it have a factory amp? If there is no factory amp then:

Yes. Run your amp speaker outputs up to the dash opening. Instead of connecting the speaker wires from your head unit to the harness, hook up the wires from the amp.

Yes this works in most situations.  It is a trick that installers use all the time.  In fact, you may look into some "9 lead wire, or sometimes called speed wire." you may even find it even easier.  it is a single 4ga shielding with 9 individual wires inside.  the 9 wires are individualy shielded and color coded the same as an aftermarket radio harness, so it is simple to know what wire is supposed to hook into what spot on the amp as well as behind the radio.  The nineth wire is for your remote wire to the amp.  it puts every wire you need in a simple, clean, well shielded, easy to run location.  You should be able to buy it at a local car audio shop. 

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If your cousin is such a good installer, and he will install anything for a 6 pack; why are you talking to me?

yeah, it will work. only exception is if your vehicle has a factory amp and in that situation you will need to run the speaker wires from your aftermarket amp to the output side of your factory amp making sure to disconnect the speaker wires from the factory amp too

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