First thing to check on a no crank with the key situation is the fusible link. It is a simple circuit as stated above. Also, I can see that all safety interlocks are out of the circuit due to the ground wire from the relay to the mounting bolt.
Before proceeding further I would also suggest gaining some more knowledge on the electrical systems in these cars. They aren't complicated, but the diagrams can look like a mess of spaghetti if you haven't learned about them first.
