GMC 1998 Savana Van Owner's Manual page 117

Mirrors
Inside Daymight Rearview Mirror
Pull the tab under the mirror toward you to reduce glare
from headlamps behind you after dark. Push the tab
away from you to restore mirror to original position.
Outside Mirrors
Adjust your outside mirrors so you can just see the
side of your vehicle, and have a clear view of objects
behind you. Some mirrors can be folded in to enter
narrow doorways.
Electric Outside Rearview Mirrors (Option)
If you have electric mirrors, they can be adjusted to
point where you want from inside the vehicle.
Then, adjust the mirror angle by pressing the outer
arrows
on the
switch until the mirror is adjusted where
you want it.
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