Make a text object, place it, and then set it up so that every 68 seconds (fnaf 1 uses 68 seconds for 1 hour), the text is set to 1 AM, or 2 AM, or whatever hour is next. Then, you make the game compare the text so that if the text reaches 6 AM, you can have another text object set up to say "Night Complete" and move on to the next layout. That's probably the easiest way.