Not sure only because I have the 4 banger. But when you look at your alternator you will see a post terminal with a ring lug and a wire on it. Usually factory wiring is 8 or 6 gauge. There is no ground on the alternator as the case is the ground following the path through the engine block.
If you don't see a wire on a post terminal than you are on the wrong bolt. You can also follow the wire from the alternator fuse directly to the location. But you won't miss it. It's usually covered with a rubber boot to protect it from shorting to ground.
Where did you end up getting some wire and for how much?