Not sure about the model numbers, but one Mavic deraileur/ index shifter combo I have (shown on the photos of my PZ-10 on the CR site) has shifters that will index either 6 or 7 speed. There are different rear derailleur cable attachments to support these two options. At least one of my Sutherlands editions discussed this.
Regards,
Jerry Moos
> My current project couples a Mavic 840 rear derailleur with 821 DT
shifters
> and a 556 rear hub (126mm -7spd). Could someone help me with what
> freewheels this get-up will index. This is my first go at the Mavic
> components. What beautiful stuff. Is there somewhere out there on the
web
> that'll help me with the history and all of these groupo's. Thanks in
> advance for your time.
>
> Dan Shindelar in MN. (it got cold again, but hard to complain this
winter)