It's not that hard really. I've popped bunches of ball joints that way, by myself. If you're lucky, it'll come apart on the first whack, but it almost always takes several whacks (maybe 3 to 6 or so), particularly if it's been a while since they've been apart.

Like Frank mentioned, make sure you loosen the castle-nut a few turns but leave it on.

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Stay the Trail!