My reply...
Yes your 2004 Ford Diesel uses the 6G Small case 110 amp alternator standard.
The most common components to fail are the Bridge rectifier and voltage regulator.
To access the bridge rectifier you remove the 3 rear thru bolts then pry the rear cover off the bearing. The rear cover comes off kinda hard, you almost need 3 hands with screwdrivers to pry it off. Once the rear cover is off you will see the voltage regulator which is mounted to the bridge rectifier. You need to unsolder the rectifier from the stator. Once this is done you reverse the procedures to put it back together. When replacing the rear cover you need to focus on getting the plastic tolerance ring over the rear bearing. This can be a problem so be careful. What I do is push the rear cover with the plastic tolerance ring over the bearing then work the housing around with hand pressure. Once I feel I have the plastic tolerance ring started I CAREFULLY tap it down with a rubber or nylon hammer. Then when installing the thru bolts be sure to tighten them evenly. Don't tighten one a whole bunch the go to the next, you will break the housing, make sure they go down evenly, using a crisis-cross back & forth pattern.