GMC SIERRA 2002 Manual page 70

There is limited space in the rear seating area of an
extended cab model. If you want to secure a child restraint
in a rear seating position of an extended cab model,
especially in the rear center position, be sure to study the
instructions that came with your child restraint to see if
there is enough room to secure your seat properly.
You'll be using the lap belt. Be sure to follow the
instructions that came with the child restraint. Secure the
child in the child restraint when and as the instructions
say. See the earlier part about the top strap if the child
restraint has one.
If your child restraint is equipped with the LATCH
system, see "Lower Anchorages and Top Tethers for
Children (LATCH)" in the Index.
1. Make the belt as long as possible by tilting the latch
plate and pulling it along the belt.
2. Put the restraint on the seat.
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