How do you pop the window out of the clamps? After trying foe multiple hours the window jusr shattered from the force applied at the "leverage" point? I did exactly what was said (atleast the part of the procedure that was actually said) I noticed after the window shattered there is a plastic retainer holding the window clips in you have to push out before applying the leverage. Is that not an important detail? Its the only thing i could come up with as to why the window shattered...