Well sometimes the third or fourth time you try something is a charm. I finally got my CentOS desktop to display on my Mac over SSH. I used this link to make it simple for me.
The key missing link is that I finally got that my local machine is the X server and that the remote machine is the client. Now I can sit outside or anywhere and manage my server using SSH command line or use the KDE Desktop. All I have to remember is that when the X11 icon shows up on my Mac after I connect to the remote server is to issue the command startkde to get my desktop.