Starter Wires

I am in process of putting in a starter. The starter has 1 tab, to connect a skinny wire to, and a large screw, to connect the "hot" lead to. The only problem is that I have 2 skinny wires in the area of the starter, but there is only 1 tab on the starter. Which skinny wire do I use? What is the other one for?
 
Thanks,
CO2 Man