You are correct.

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BONASERA (as he leaves the room)

Grazie, Godfather.

VITO CORLEONE

Prego.

(then, to Tom Hagen, after Bonasera leaves the room)

Ah, give this to ah, Clemenza. I want reliable people; people that aren't gonna be carried
away. I'm mean, we're not murderers, despite of what this undertaker says.
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Perhaps he was a member of Clemenza's crew 10 years earlier. In any case, either this is an error or somethign that should have been better explained.

When the Boss tells me to push a button on a guy, I push a button. See, Senator?