When Arnold and Gerald go to the secretary to find Mr. Smith's office so they can deliver the package to him, the secretary can be seen with exposing cleavage, but as she presses the button for security, her whole torso is covered.
When Arnold and Gerald are disguised as one, Gerald says, "Arnold, hang on to that pipe for a second.", to which Arnold replies, "Huh? What are you, nuts!?". The second line is spoken in Arnold's voice, but yet, Gerald's mouth is the one that moves.