Use the fork, sometimes its the only way.
5 steps to seperate the LCA from the balljoint stud:
Step 1: Take the castle nut and skrew it onto the balljoint threads just enough so that it's sticking of the end of the stud.
Step 2: take a floorjack and jack up on the balljoint stud (the nut is there to protect the threads), compressing the suspension
Step 3: Take the pickle fork, insert it between the joint and the lca (flat side towards boot), locate a BFH and proceed to pound the **** out of it (reminder: you hit the end of the fork to drive it into the joint, not down on it to try and pry it apart). If the fork kinda works it's way towards the dust shield and wedges in there, thats good, it'll direct all the pounding into the joint.
Step 4: dont give up, just keep hitting that f**ker as hard as you can until it seperates, it'll eventually go with a big bang that'll wake up your neighbors, as will your cries of relief.
Step 5: clean up all the grease thats puked out of the boot and squirt some new grease into the boot to replace it.