GMC Yukon Denali 2003 Owner's Manual page 66

Yukon Denali models: A child restraint with a top
strap should only be used in the second row or third row.
Don't use a child restraint with a top strap in the right
front passenger's position, 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 and in the outboard
passenger position in the third row for 50/50 split seats.
Yukon Denali Third Row 50/50 Split Seat
Yukon Denali Second Row Seat
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