GMC Chevrolet Tahoe 2003 Manual page 29

Once the seatbacks are folded down, the rear seat
footwell area will be exposed and will have to be
covered by the load floor panel. To create a load floor,
do the following:
1. Release the panels from the seatbacks by pushing
forward on the latches.
2. Then fold the panels back to cover the rear seat
footwell area.
If you have removed the head restraints to fold the rear
bucket seat, be sure to reinstall them on the seatback
after it has been returned to the normal seating position.
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