FORD 2002 Thunderbird v.1 - Manual (Page 128)

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.
1. Position the child safety seat on the passenger seat cushion.
2. Locate the tether anchor at the
bottom back of the passenger seat.
3. Route the child safety seat tether
strap under the head restraint and
over the back of the seat.
Seating and safety restraints
128