Adding Line out converter in 2000 Saab 9-5 Sedan?

Hello everyone just one quick question. I'm planning on installing an amplifier so I can install a subwoofer in my Saab. I was wondering if I could install a line out converter by tapping into the rear speakers instead of the head unit to add RCA inputs for the amplifier. Here's the one I have in mind... http://www.sonicelectronix.com/item_23128_PAC-SOEM-T.html



Thanks!Adding Line out converter in 2000 Saab 9-5 Sedan?
that'll do it. done this myself plenty of times. PAC is a good brand also.

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