Since this winter is not co-operating when it comes to driving the car I broke down and bought a battery tender. Reading through the instructions it talks about positive ground systems and negative ground systems. I am assuming that the Crossfire like my other vehicles is a negative ground system and as such the positive (red) clip gets connected to the positive terminal and the negative (black) clip connects to the chassis. Just trying to make sure the Germans do not do it the other way. I know I am over thinking this.