Big 1959 and CarlieIsaiah, the pic shown of Big's starter may help you both. That is an unsafe condition. Make sure (no, make **** sure) that the cable from the battery + to that largethreaded lug has a thin insulating washer between it and the starter case. Also check to see that hole in the terminal of that + cable is the correct size to just fit the large threaded lug, not worn over-sized. Then, get a 90 degree rubber boot to fit onto the cable and over the lug and wires. The large threaded lug should have once small wire on it sandwiched OVER the battery cable. That small wire go back to the ignition switch "run" pole, then back to the rectifier -- this serving to send charge current to battery. The start position of the ignition switch has its wire going to the exposed small pole of your starter, it connects with a small round eyelet terminal and small bolt AND also needs a smaller rubber 90 degree boot to be safe. If you still need the wire colors, I can go take a look at my 1982 650 which is locked up in its garage right now. I will be using it tomorrow. I recently replaced the generator, the rectifier, and the 6 pin connector at the rectifier and had to trace all of this. But, I do not remember the colors off hand, but all of mine are original colors. BTW, it is not particularly safe, but you can start your tractor by jumping a wire from that small terminal to the large one, or bridge them with a screwdriver. Make sure it is in neutral and brake set firmly and PTO off and hydraulics down. You are at your own risk with that short cut (pun intended).
prs