Chevrolet 2004 Express Van Owner's Manual page 55

If your vehicle is a passenger van with rear seats, an
anchor bracket for a top strap is located at the rear
of the seat cushion for each three-passenger rear bench
seat. Don't use a child restraint with a top strap in the
right front passenger's position, or in any four-passenger
rear bench seat.
The top strap is designed for the second row driver side
position and the third/fourth row center searing
positions in a three-passenger rear bench seat.
Passenger Van 3–Passenger Rear Seats
Anchor the top strap to this bracket. For the second row
only, in the left outboard seating position, use anchor
point (A). For the right outboard seating position,
use anchor point (B). For a center seating position, use
either anchor point (A) or (B).
Lower Anchorages and Top Tethers
for Children (LATCH System)
If you have a passenger van, it may have the LATCH
system. If it does, you'll find two sets of anchors (A)
in the second row of seats in the driver and passenger
side seating positions, where the seatback meets
the seat cushion.
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