I'm planning to lower the bass on all the speakers and add a sub. I definitely don't have an 8 inch LCD and I don't see a Sony branding anywhere so I guess I would have a stock Sync radio. Is there a sub output either amp or pre-amp coming out of the stock unit? If so, how do I turn it on? Should I expect wiring behind the rear seats for the add-on sub that I could use for my inputs?

Thanks for any help that can be offered. I just couldn't find definite answers reading other posts!