97 e250 5.4l starter really stupid question

Ok, so I had a friend of mine drop off a 97 e250 cargo, 5.4l v8, that needed a starter installed. The starter had already been pulled and swapped for the core charge.

I have 3 cables coming down to the starter hook up. I know one is positive to the battery, 1 is the switch connection. Does that negative cable go directly to the starter, or is it a body mount ground?