Electrical/starting problems

The smaller stud on solenoid of starter, goes to small stud on starter relay (S5 #12 Brown). The (A1A #10 Black) wire from battery +, goes to big stud on starter relay. I think your description or wiring is in error.

It is possible to use replacement terminals, with crimp and bolt connections. I did a post a few months ago. A tale of battery cables