2007 GMC Sierra 1500 Pickup Owner's Manual - Page 62

Extended Cab Regular Cab For regular cab models with a bench seat, the top tether anchors are located under trim covers on the back panel behind the center and passenger seats. Do not install a child restraint in the center seat position. See Securing a Child Restraint in the Center Front Seat Position on page 74 for more information. For regular cab models with bucket seats, the top tether anchor is located under a trim covers on the back panel behind the passenger seat. Remove the trim plug to access the anchor. 62 For extended cab models, the top tether anchors are located near the top of the seatback for each rear seating position. In addition to the top tether anchors, each seating position has a fabric loop at the top of the seatback that you will use to route the top tether through. Be sure to use an anchor located on the same side of the vehicle as the seating position where the child restraint will be placed.