73 Dart Alternator doesn't show charge anymore.

All the connections appear to be alright on whatever this is, it's not that I'm worried about I just am not sure why it's spliced into a fuse and what it's *actually* supposed to be connected too, I can't really look at the diagram for it because I don't know what it is, if it is the brake lights it's supposed to be on fuse 4 and not fuse 5, if that matters, they should be the same power source.