Put it last in the edit, after the final scene, and use the Law and Order Dun Dun sting just before it to mark the close, then let this clip finish the sequence on its own.
關於此聲音
This is a brief spoken sign-off lasting about three and a half seconds, built around one clear voice saying good night to America. It feels warm, final and a little theatrical, like the last line before the lights go out. The short, direct delivery makes it easy to recognise and gives it a calm, closing mood for the end of a night.