1. Disconnect the negative wire on the battery.
2. Remove the power supply, and connector from back of alternator.
3. Put wrench on belt tensioner, and remove the belt. Take a note, or a picture of it's path.
4. Remove 2 bolts that hold alternator in place.
5. Get big pry bar, pry alternator out.
6. Installation is reverse of removal. I think the bolts are torqued to 22 ft/lbs.
Keep in mind, the alternator is a very tight fit (as is the space you'll be working in), and will take some wiggling to get into place, and probably the pry bar to get it into place. You may have to remove the pulley of the power steering pump to get to the lower bolt of the alternator. Be careful of the thermostat housing behind the alternator when you're removing the power wire on the alternator.
You may have to remove a little more to get it out, but this should assist. Let me know if you've got any questions, I can always refer to my Bentley.