I just spoke with JL technical support. They said that the best way to hook up a sub (if it's similar to the G35) is to tap off the amp wires going to the Bose OEM subs from the stock amp. He said the amp is in the trunk as explained in the JL website for the "Stealthbox" installation for the G35. Is the amp in the same location as the G35?? His concern with tapping off the 6X9's was getting the correct frequencies from the sub I'd be installing. I know that several forum members have just tapped into the rear deck 6X9's with success....Is the JL tech guy not correct ....is it worth the effort to tap off at the amp?? Thanks so much for the info so far and for answers to this post.............New cars are always an adventure!!