BAK Revolver X4s Hard Roll-Up Tonneau Cover for 2020-2026 Chevrolet Silverado / GMC Sierra 2500-3500 HD (6'9" Bed)

Here's the short version. Follow BAK's install sheet (below) for your truck's exact clamp and bracket positions.

1. Seal the bulkhead. Clean the top of the bulkhead with soap and water, then isopropyl alcohol, and let it dry. Stick the seal flush with the front edge, snug between the bed rails: the 3/4" seal on a truck without a drop-in bedliner, the 1/4" seal on one with a drop-in liner.
2. Set the first rail. Place the passenger rail on the bed rail with its slotted bracket pushed all the way to the cab. With a drop-in liner, remove the foam pads at the front of the slotted brackets; some liners need their corners trimmed.
3. Clamp both rails. Fit the first clamp 12" or less from the front, the second near the middle (two in the middle on 8' beds) and the rear clamp less than 12" from the tailgate. Press the rail down, keep it square and level, and tighten each to 10 ft-lb with a 9/16" socket. Over-tightening can warp the bed cap. Repeat on the driver side.
4. Set the cover on the rails. Rest the rolled cover on the rails at the tailgate, roll it toward the cab and throw away the packaging. Fold the front panel back, drop the two mounting bolts on each side into the slotted brackets, then fit the rubber washer, large flat washer and lock knob underneath, loosely for now.
5. Square it up. Roll the cover open and closed a few times so it runs freely. Line up the front vinyl edge with the front of the rails (not the rubber seal) and keep a gap of about 1/8" (3.2 mm) on each side. Both slam latches must meet the locking levers squarely at the tailgate.
6. Lock it in. Roll the cover open without knocking it out of line and tighten the knobs by hand only. Close it and check the locking levers hold it down on both sides. Stick the four D-shaped bumpers to the slats so the rolled cover can't touch the cab, and mount the strap clamps as far forward as possible at 10 ft-lb.