Are you just trying to release the tension on the drive/serpentine belt? If so, the nut you'd want to put the 14mm wrench on is on the automatic belt tensioner pulley. That pulley is located just above and between the generator pulley and the crankshaft pulley.

Once you have the wrench (or socket w/ratchet) on that nut, lever it clockwise to release the tension on the belt.