brakes not working right

It's a '73 car. As I stated in response to another post, the engine is at least '76, different heads than earlier, the rear end is possibly '72, which may be part of the problem now that I think about it, and the drivers door is from a different car. The window stabilizing part bolts on differently and is missing, so I don't know what year it's from. But the majority, the body, is '73.
You basically want to download the 73 manual at MyMopar. It then matches the body/ wiring. The other parts you mentioned are essentially the same