It more strongly points to the need to start with the basics. What the heck good is a wiring diagram when you haven't taken the first steps of the most common failures.
Step 1a: Check the grounds. That doesn't mean eyballing whatever; verify that the lights are grounded.
Step 1b: Check the brake light switch. It's just above the brake pedal.
Another bad day for Amervo I guess. He must have forgotten that some folk are just getting their feet wet in vintage automotive repair.
As suggested, I would invest in a good multi meter (VOM) and learn enough to be dangerous. Just kiddin'. Electrical problems can be solved with a little know how and the right tools. You have to provide the tools, we can help with the know how. I for one won't blast ya for not knowing where to start. There's no such thing as a stupid question, there's just stupid answers.