Pontiac 2006 G6 - Manual (Page 51)

Retractable hardtop models do not have top tether
anchors in any seating position.
Do not secure a child restraint in the right front
passenger’s position in a coupe or sedan model or in
any position if your vehicle has a retractable hardtop, 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 these positions.
Accident statistics show that children are safer if
they are restrained in the rear rather than the front seat.
See Where to Put the Restraint on page 1-39 for
additional information.
Coupe
1-45