Continuity mistake: Mike is sitting in a diner as a waitress is walking up to him. The shot is from outside the window and shows the reflection of a mixed race couple walking across the street towards the window. When the shot changes to the waitress coming up and bringing him his drink, there is suddenly nobody in the street at all or around that could have been making that reflection. (00:31:20)
Answer: The bulldozer could be disassembled, the individual pieces carried down, and then reassembled once underground.
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