I'm breaking in, shaping up, checking out on the prison bus
To tie it in to the previous line, it could just be a regular bus that takes the average American to their mindless job. They just commute back and forth everyday without any thought until they just do it automatically. All this makes them feel trapped, like they are actually imprisoned. This contributes to why the narrator only sees the world as a shit hole. But he wants to “break away” and “eject” from that way of thinking and make something of his life.
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