Factual error: When Mike is waiting in the parking garage with Sobchak for Pryce to arrive, the AT&T logo is prominently displayed on an office building in the background. This logo is the new style introduced in late 2005 and didn't exist in 2002 when the show is set. (00:11:25)
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.
Answer: The bulldozer could be disassembled, the individual pieces carried down, and then reassembled once underground.
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