Chevrolet 2000 Tahoe Owner's Manual page 66

Suburban/Yukon XL Third Row Seat
Utility models: A child restraint with a top strap should
only be used in the second row. Don't use a child
restraint with a top strap in the right front passenger's
position or in the third row, because there's no place to
anchor the top strap.
An anchor loop bracket for a top strap is located at the
bottom rear of the seat cushion for each seating position
in the second row.
Utility Second Row Seat
Anchor the top strap to this bracket. Once you have the
top strap anchored, you'll be ready to secure the child
restraint itself.
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