How does push to remove key collar work??/

I am converting my column shift steering column to a floor shift column in my 71 Barracuda. I believe I have all the right collars and parts. I have already removed the inner tube and installed the spring washer that the bottom collar sits on. I can't figure out how the push to remove key collar works. I must be missing a lever or something. Does anyone have a picture of the pieces or a good description of how it works?

I posted this on the E-body site but this site is better!

Thanks