So all appeared to be going quite smoothly with a master cylinder replacement on the '68 Dyane until starting to put it back together and the actuating rod seems too long. (So probably not so smooth then!) It doesn't go as deep into the new master cylinder as it does in the old one. I don't think that the adjustment nut will take up the slack (and I couldn't shift it easily either) All of the other connections appear correct. I was reluctant to start getting the saw out so thought I'd try asking for advice... Many thanks for your suggestions.
201610_MasterCylinderChange by ipacey, on Flickr