Pontiac 2005 Montana SV6 Owner's Manual page 27

For ease of installing the seat, put the seat in the folded
position before beginning this procedure.
1. From the rear of the vehicle, place the front hooks
of the seat onto the front floor pins in the third row.
To do this, the seat will need to be angled
approximately 8-10 inches (20-25 cm) from the floor
so the front hooks clear the rear floor pins and
rear floor cups. Use the release handle to guide the
seat into place.
If the front hooks are not attached correctly, the
rear latches will not attach to the rear set of
floor pins.
2. Firmly push the rear latches into the rear floor pins
by pushing down on the rear of the seat.
3. Try to raise the seat to make sure that it is locked
down. The indicator pins will no longer stick out
when the seat is properly latched into place.
CAUTION:
{
If the seatback is not locked, it could move
forward in a sudden stop or crash. That could
cause injury to the person sitting there. Always
press rearward on the seatback to be sure it is
locked.
4. Return the seatback to its upright position. See
"Returning the Seatback to an Upright Position"
earlier in this section.
1-21