I found the 6400 instruction on line back when I first got a working set from cudak888.
There have been several PC's since then, so they're long gone, but I think I was searching for "how to shift Shimano Total Integration" and the manual came with the site...

before that, I'd taken the bike to LBS and asked them how to shift. The local bike goddess at the time just smiled and explained it. I know they laughed like crazy after I left. She's still a goddess among women (pretty, smart, and can overhaul bikes), but since she told me she finally "gave away about 7 sets of new Campy wheels, probably 20-30 years old" to a rep for GT or something...I've downgraded her to "just great."