I just went through the same thing.....I spent forever trying to WD40/rubber mallet the thing apart; finally (after a wasted day of trying to separate 'em), I picked up some hardened stud removers, hammered them on, and racheted the studs out. I guess a leaky gasket had let some fluid rust the whole thing assembly together. So anyway, 4 new studs from ford cost just over 20 bux, and after quite a bit of cleaning and dremeling, it was all like new.