Hello Dan
Your 2015 Chevy needs part number AMP74815-01A. The depth is about 2 feet and it will come out to the edge of the tailgate. With it flipped inward it will sit down and clear the wheel wells on a 6.5 ft bed. On a 5.5 ft bed it will contact the wheel well. I hope this information is helpful. Thank You for your question.
Jon Snyder 4wheelparts