I have a thread from the other photo site bookmarked:
http://photo.net/film-and-processing-forum/009ajI

The thread concerns processing Kodachrome at home, and while step by step instructions don't exist, I've figured that the closer we get to Jan 1, 2011 the more likely someone will figure out and post the chemistry and steps necessary for hand development of Kodachrome, since not all rolls of K-chrome out there are likely to be sent in before time. Personally, 120 K-chrome sounds pretty neat, if it were me and I were feeling particularly ambitious, I'd try to process them by hand after figuring out the right chemistry and steps.