Personally, I would go with a pre 95 if your friend wants to do modifications to it. There is more available for older ex`s, but there is more stuff coming out every day. up to 95 the 4x4 came with a dana 35 front axle. After, they have kind of a strut type setup(?)
Apparently there is trouble getting suspension lifts and front lockers for the newer models, but again, that may soon change.
Find one with a manual tranny (the ford autos suck a little more than the mans.) I got 4 inches total lift out of my 93 for less than 300$ -doing my own work.
I would also get manual hubs, I hear there is a lot of problems with those pushbutton setups.
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