Locking ring

You'll need a special tool which doesn't cost very much. Anything else will be met with frustration. The tool is a threaded shaft that screws onto the steering shaft. A metal bracket slides on over the tool so its two fingers push down on the lock ring. A nut is threaded onto the tool to push the lock ring down. That gives you hands-free access to pry the wire ring off. With the ring off, the lock plate will lift off when the tool's nut is unthreaded. I think I can find a picture of the tool if you need it.

If you go to this link, it's the 12th item down the page. This is from Mac Tools and costs $51.99. If you have a Harbor Freight Tools nearby, they will have it too for a lot less. The spacing for new paragraphs isn't working yet on this site so I can't make the link stand out. It starts with the "http" and ends with ".aspx". I'll put it way at the end.

I don't have the black part of the tool. That must be an extension for some applications but I've never needed that. All you need are the two silver parts.

http://www.mactools.com/productdetails/tabid/119/c-23000-specialty-pullers.aspx

Forgot to mention that a lot of auto parts stores rent or borrow tools and will likely have this one.