as you're looking at the pulley, the very left hand side tick is -5 from there it goes 0, 5,10,15.... so you want to put it at or a little before the 5th mark to get 13-15 deg
Nissan Forums is the go to place to talk about your favorite Nissan model, including the Rogue, Maxima, Altima and even sports cars like the 370Z and 200SX.