Mike gets ahead of himself and tacks in the trunk floor extensions before replacing the rear crossmember brace (the new crossmember hasn't arrived yet, and Mike's not one to sit around and wait). The whole back of the Charger is "woven" together during construction, and everything interlocks. The rear brace goes behind the back of the trunk floor extension and attaches to the top half of the valance, which goes on after the trunk floor extensions. You'll have to pry pieces into place in several instances while replacing the rear sheetmetal on a Mopar, so pay careful attention to how it comes apart. Once everything is located, the brace is spot welded into place.