The rear speakers are REALLY exposed to sunlight. If the previous owner didnt replace them, they are a paper cone speaker stock and are probably sunfaded and worn out. You definitely wont get any benefit from going back to 1987 20 year old technology. My advice is to check the speakers first, then bypass the factory amplifier by rewiring from the headunit back. Lather, rinse, repeat. If you need any help doing any of this, lemme know...
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