A Little Ball Joint help Please

[DT1]

I took the 71 in for alignment and was told the upper right ball joint was worn, so I bought a complete set of Moog upper and lowers. The joints popped out OK but I can't get the lower joint off of the A Arm. It looks like it should be simple. I looked at the new one and all there I see is a serrated collar that needs to be pushed out of the arm. I supported the A Arm with some wood and fit a piece of pipe over the joint so I could smack it out. Not happening! Any tricks to it or should I get a bigger hammer??