GMC Yukon Denali 2006 Manual page 69

For Regular models with third row seating, there is
one top tether anchor located at the bottom rear of the
seat cushion that can be used for either the center
or passenger side seating position in the third row, but
not for both. Never install two top tethers using the
same top tether anchor.
Third Row Seat — Regular Models
For Extended models with third row seating, the top
tether anchor is located at the bottom rear of the seat
cushion for the center seating position in the third row.
Third Row Bench — Extended Models
For Regular models, do not secure a child restraint in the
right front passenger's position or the third row driver's
side seating position 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. There is no place to attach the top tether in this
position.
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