It’s light out, I had a few minutes, and it almost hit 20 here, so I crawled under my truck in the parking lot at work and took a few shots of what mine looks like. From what I could see
@legmar, you were looking at the passenger side. From what I remember, the outward facing side of the “box” is open. This should allow you to push the tubing straight through until it hits the bed panel. At this point if your arms are long enough, reach up and help it make the turn towards the ground. If not use a coat hanger or something to fish it down. It helps to have a “pusher” and a “puller.” (I recruited my wife for assistance). You may notice I had cut this side short prior to establishing this game plan, but I would recommend leaving it long.
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The drivers side is similar but a little more complicated because the fuel and def filler box is in the way. Use the same technique but be sure to fish it as straight as possible around everything. It’s definitely important to leave it long so it will reach past the box and to the ground. Hope this helps. Let me know if you have any other questions. It took me looking under there to jog my memory on the install. ???
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