I'm not sure what is all involved on the 4x4. On a 98 2 wheel drive with the coil spring suspension, there is no caster/camber adjustments. All they do is adjust the toe in, something that can easily be done at home.
Last year I had my 2001 3.0 4x4 aligned. Cost me $75 and from what I can tell they really were only able to adjust the toe. The caster/camber adjustments needed an adjustment kit installed for more added expense (can't remember how much more but it seemed like it was enough). I told them to check the alignment first and see if the kit was even needed. Turned out everything was within spec on the caster/camber adjustments so I passed on the install, maybe next time I won't be so lucky. I'm not a fan of this nickel & diming Ford is pulling on us but I was assured by the alignment guys that all the car companies are doing it. I can't verify that because all I have is Fords.