Two options I would recommend.
1) Go to http://repair.chiltondiy.com/Nissan/Quest/Repair-Manual-Online for an online step-by-step repair guide.
2) Go to Auto parts store, ask for Chilton or Haynes repair guide for your vehicle.
3) Worst case scenario. Buy the new part, look and see where bolts are located on the new one and take the old one off.