Chevrolet 1997 Astro Owner's Manual page 58

10. Pull up on both shoulder harnesses to tighten the lap
parts of the harness.
11. Adjust the position of the harness on the child's
shoulders by moving the clip up or down along the
harness. On each side of the harness, the shoulder
part should be centered near the child's shoulder.
The harness should be away from the child's face
and neck, but not falling from the child's shoulders.
If you expect that the child will sleep while riding, you
can recline the seatback. See "Seats" in the Index.
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