I was at a build party and one of the guys there had the theory that the trick is getting everything square. He uses a variety of washers to support the trunnions so that it was as square as possible to the pressing pin.
I posted pics of what I use to remove the pins here:
http://www.quarterbore.com/images/amdbuild1/
The bolt has two nuts on it. One on the inside sets the length of bolt and it is set so that the head of the bolt is flush with the socket head. The second nut is tightened down with a wrench so there is no give! IMPORTANT NOTE, THE BOLT HAS ALL THE FORCE - NOT THE SOCKET!
Now, I have bent a few of these short Grade 8 bolts and then it is time to take the grinder and cut the bolt off and start again but this works for me.
Just add some penetrating oil, line everything up, apply pressure and give the base of the jack a whack with a hammer. Add a little more penetrating oil if needed, add more pressure and give it another whack. Often the WHACK with the hammer is when it will pop!
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