A Greyhound bus' roof was sheared off when the driver ignored signs about an overpass that was lower than the bus' height. Passenger William Tedeschi said, "All that we heard was a big rip coming from the front to the back. I thanked God I was alive -- I was so scared." The bus was stuck at the overpass on the Henry Hudson Parkway around West 252nd Street. Six passengers were injured by the debris;......