Chevrolet 1999 Monte Carlo Owner's Manual page 42

3. Be sure that the belt is not twisted and it lies flat.
The elastic cord must be under the belt and the guide
on top.
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4. Buckle, position and release the safety belt as
described in "Rear Seat Outside Passenger Positions"
earlier in this section. Make sure that the shoulder
belt crosses the shoulder.
To remove and store the comfort guides, squeeze the belt
edges together so that you can take them out from the
guides. Pull the guide upward to expose its storage clip,
and then slide the guide onto the clip. Rotate the guide and
clip inward and in between the seatback and the interior
body, leaving only the loop of elastic cord exposed.
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