As you have seen from everyone, getting the ball joints out of the knuckle suck. If you mean by hand, in using a big ratchet or a huge breker bar, then good luck. I was in my buddies shop that he works on Jeeps all the time in, and he has a guy that builds diesel transmissions out of. He has a decent ball joint kit, which we used, and to have enough power to pop them out, we ended up using a 3/4 inch air impact wrench. I was able to press the first 2 out by hand, using a 24" breaker bar, with it in a vice, and him holding the knuckle and tools steady. I really had to LEAN on the breaker bar. Now to explain my LEAN, the wrench was about shoulder high, and I go about 350-375lbs and it took me pulling and pushing with everything I had, to get it to move...... which is why we used the big impact.
I'm hoping when I replace them here soon, for a second time, maybe they won't be so hard to get apart........