How do you replace the alternator on a 1989 Nissan 240SX?

Drive the car up onto ramps or jack the car up to change the alternator you need have access from the bottom of the engine. Access to the alternator is very tight. First disconnect the battery. Accessing from the top loosen the drive belt and remove the adjusting bolt, ground wire, battery wire and plug in connector from alternator, do this before removing the bottom bolt from alternator. Once bottom bolt is removed the alternator is to be taken out the bottom, it is a tight but it will come out. Hope this helps.