Pontiac 2004 Montana Owner's Manual page 399

5. Push the release clip at the connecting point of the
blade and the arm up. Then pull the blade assembly
down toward the glass to remove it from the
wiper arm.
6. Push the new wiper blade securely on the wiper arm
until you hear the release clip "click" into place.
7. Push the release clip, from Step 4, down to secure
the wiper blade into place.
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