GMC 2003 Sonoma Owner's Manual page 273

3. Release the hood prop from its retainer and put the
hood prop into the slot in the hood.
Before closing the hood, be sure all the filler caps are
on properly. Then lift the hood to relieve pressure on the
hood prop.
Remove the hood prop from the slot in the hood and
return the prop to its retainer.
Then, pull the hood down firmly to close. It will latch
when dropped from about 10 to 12 inches (25 to 30 cm)
without pressing on the hood.
5-11