GMC 2004 Envoy Owner's Manual page 53

A rear seat is a safer place to secure a forward-facing
child restraint. If you need to secure a forward-facing
child restraint in the right front seat, you will be using the
lap-shoulder belt to secure the child restraint in this
position. 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.
1. Because your vehicle has a right front passenger's
air bag, always move the seat as far back as it will
go before securing a forward-facing child restraint.
See "Seats" in the Index.
2. Put the child restraint on the seat.
3. Pick up the latch plate, and run the lap and shoulder
portions of the vehicle's safety belt through or
around the restraint. The child restraint instructions
will show you how.
4. Buckle the belt. Make sure the release button is
positioned so you would be able to unbuckle the
safety belt quickly if you ever had to.
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