Continuity mistake: When Jimmy is talking outside the courthouse, pretending to be his secretary, he puts his case on his car roof. In the first shot the white aerial is visible in front of his case. Shortly afterwards it's hidden, either behind or on top of his case, without him touching anything.
Continuity mistake: After James hits the roller blade guy, when the two brothers run away the sun changes between shots.
Answer: The bulldozer could be disassembled, the individual pieces carried down, and then reassembled once underground.
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