Pontiac 2005 Montana Owner's Manual page 31

Make sure the seatbacks are in the upright position, the
seat belts are on the correct side of the chairs and
the second row captain's chairs are in the full rear
position before beginning this procedure.
1. Hook the front latches over the front floor pins.
2. Push the rear of the seat down to lock the rear
latches onto the rear set of floor pins.
3. Push and pull on the seat to be sure it is
properly attached.
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