I think Bally schematics are the easiest ones to read. Anyway for the score motor switch notice how it says 5f? That means it's the 5th cam from the physical motor itself. F usually means the 6th switch from the bottom of the stack where A is first (lowest), B is the second Etc.
All of that said it's very easy to follow the wire color code on the schematic. That's the Little Numbers in the Little Boxes by each wire there is a table that shows what each number represents as far as wire colors go. There is also a table of score motor cams usually on the side of the cabinet or on the schematic.