Under the passenger seat. Just got finished installing 5 gauge wire (Walmart special) through the passenger side firewall. I will try to bolt it down since some sick bastard took my wife's radio (6 year old Ford Taurus Wagon

) during the night. The theif did not touch the titan which was parked outside due to a custom subwoofer box I was building in my garage. I don't feel so bad since my deductible is $100 for my car and $50 for the Titan.