PHILADELPHIA — The Philadelphia 76ers may as well have won the NBA championship when they dethroned the Boston Celtics in the east. The delirious Sixers fans stormed the court and swarmed Wilt Chamberlain. One fan even hung on a rim as the players hustled past outstretched arms to the locker room. The Sixers popped champagne against the backdrop of a fan-made “1967 NBA champions” poster tacked to the wall. The Celtics dynasty — for a year, at least — was dead. Long live the Sixers. Chamberlain, the agile and dominant center of his era, put an end to the hooting and hollering and silenced the Eastern Division championship revelry with a brief speech: Philadelphia still had one more goal to achieve. “The room got very quiet,” Sixers great Billy Cunningham said. Chamberlain’s big point was this — the Sixers didn’t win 68 games and knock off the hated Celtics just to squander their shot at an NBA championship.