you already have a subwoofer.... its a three incher in the right trunk compartment.
in theory you could (but not recomended....) locate the stock woofer leads and put then on an aftermarket woofer, but its doubtful that the bose amp could power a full sized sub.
your best bet is get an aftermarket head unit to run the speakers, and run a seperate amp for the woofer. With an aftermarket head unit, the bose amp will still power the speakers, and with the reduced power running to the tiny sub, your speakers will be alittle more powerful. Be sure to disconect the stock woofer if you go this rout.
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