I've used this tool box in both a 2002 Frontier and a 2012 Frontier. I had the bottom corners folded in and re-welded so it would fit the wheel well of the gen 1 Frontiers. On the gen 1, the sides rested on the bed rail and bolted in. On the 2012 I used unistrut parts to mount the box into the Utili-Track. I had lighting inside of the box, so there's two holes to get wires into the box on the back. Happy to seal those up if you don't intend to use them.

Cash or Venmo.