Sheldon Brown and Harris
to the rescue (scroll to the bottom).
What I'ld like to know is how do you know if you have a pre '82 w/o destroying it? I have a Stronglight 93 from a raleigh, want to put it on my Gitane TdF that came w/o a BB. If I can screw on the Park tool easily, does that mean it's the 22mm?
Fun!