GMC 2000 Safari Owner's Manual page 248

CAUTION:
Getting under a vehicle when it is jacked up is
dangerous. If the vehicle slips off the jack, you
could be badly injured or killed. Never get under
a vehicle when it is supported only by a jack.
CAUTION:
Raising your vehicle with the jack improperly
positioned can damage the vehicle and even make
the vehicle fall. To help avoid personal injury
and vehicle damage, be sure to fit the jack lift
head into the proper location before raising
the vehicle.
7. Raise the vehicle by turning the ratchet clockwise.
Make sure the UP mark faces you. Raise the vehicle
far enough off the ground so there is enough room
for the spare tire to fit.
8. Remove all the wheel nuts and take off the flat tire.
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