Peter, Quagmire and Joe get back into the Clam by using a side entrance window situated in an alleyway. Other shots show the clam is adjacent to two buildings, both taller than it and there is no such alleyway.
During Peter's speech to the players before the softball game, one of the shots shows the "Drunk Clam" writing on one of the other players overlapping Horace's arm.
When the 2 business men walk through the Griffin's front door, the door swings out instead of in.