Buick 2002 Regal Owner's Manual page 242

The tools you'll be using include the jack (A), extension
and protection guide (B) and wheel wrench (C).
Removing the Wheel Center Caps
To remove a center cap, use
the wrench to pry gently at
the notch. Don't use a tool
that is narrower than the
wrench to pry at this notch.
Then pry off the cap.
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