Buick 1998 Century Owner's Manual page 12

Reclining Front Seatbacks
Lift the lever to release the seatback, then move the
seatback to where you want it. Release the lever to lock
the seatback into place. Pull up on the lever without
pushing on the seatback and the seatback will
move forward.
But don't have a seatback reclined if your vehicle
is moving.
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