GMC 1994 Yukon Owner's Manual page 301

Center High Mount Stoplamp (CHMSL)
The individual bulbs
in the CHMSL are not
replaceable. See your
dealer for assistance.
Rear Lights
1 . Open the tailgate or rear doors.
2. Remove the two black plastic plugs in the rear light assembly access
3. Remove the two
rear light
assembly screws
inside the fender
and pull out the
light assembly.
You may want to
use a magnetic
screwdriver when
removing the
screws.
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