I've helped drop a few rudders. Where are the pics and what is the question?

:: I have some pictures of the top of my rudder "shaft."
:: The piece that the tiller assembly bolts to, is
:: something of a mystery to me. Could use some help
:: figuring out how to disassemble so I can drop the
:: rudder. Don't want to break anything or use a hacksaw.

:: Thanks,

:: J