GMC 1998 Safari Owner's Manual page 64

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.
1. Unfasten the shoulder harness clip.
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