Buick 2003 LeSabre Owner's Manual page 345

2. Slide the rear of the cushion up and under the
seatback so the rear-locating guides hook into
the wire loops on the back frame.
3. With the seat cushion lowered, push rearward and
then press down on the seat cushion until the
spring locks on both ends engage.
4. Check to make sure the safety belts are properly
routed and that no portion of any safety belt is
trapped under the seat. Also make sure the seat
cushion is secured.
1. Buckle the center passenger position safety belt,
then route the safety belts through the proper slots
in the seat cushion. Don't let the safety belts get
twisted.
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