Chevrolet 2008 Colorado Owner's Manual page 51

Extended Cab — Rear Seat
The top tether anchors in an extended cab model are
located on the center of the back wall behind a removable
cover for the rear seating positions. Be sure to use an
anchor located nearest to the seating position where the
child restraint will be placed.
Regular and Extended Cab without Rear Seats
For regular and extended cab models without rear
seats, there is a top tether anchor located behind a
removable cover on the back wall behind the right front
passenger seat. You may have to pull the seatback
forward to access the anchor.
Do not secure a child restraint in a position without a
top tether anchor if a national or local law requires that
the top tether be attached, or if the instructions that
come with the child restraint say that the top tether
must be attached.
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