FORD 2010 Mustang v.1 - Manual (Page 155)

The tether strap anchors in your vehicle are in the following positions
(shown from top view):
Attach the tether strap only to the
appropriate tether anchor as shown.
The tether strap may not work
properly if attached somewhere
other than the correct tether
anchor.
Once the child safety seat has been
installed, using either the safety
belt, the lower anchors of the LATCH system, or both, you can attach
the top tether strap.
Perform the following steps to attach a child safety seat to the tether
anchor:
For Coupe only:
1. Route the child safety seat tether strap over the back of the seat.
For vehicles with adjustable head restraints, route the tether strap under
the head restraint and between the head restraint posts, otherwise route
the tether strap over the top of the seatback.
2. Locate the correct anchor for the
selected seating position.
2010 05+ Mustang (197)
Owners Guide, 1st Printing
USA (fus)
Seating and Safety Restraints
155