Originally Posted by
stingx
I initially just wanted to get a group that would make it period correct but thought I'd add a more modern drive. My LBS can cold set the frame.
I'd go with jeirvine's suggestion of using 7spd cluster and just avoiding the last click. I'm not a fan of cold setting a nice old frame, more on principle than whether or not it would work. My GC has SR derailleurs and a Regina Extra 7-sp freewheel. It shifts just fine.
It sounds to me like your bigger issue is brifters vs downtube shifters. I set up a Trek with Accushift levers, a SunTour Vx derailleur, and SunTour 6-speed freewheel. Shifted just fine. If the pull ratio of your derailleur is the same as the Veloce brifters, you might be able to work. It would be fun to try (well, I think it would be fun), and if it fails you can still go the cold set route.