I raced with a Jubilee on my custom road frame back in the late 70's and I don't recall any major compatibility issues with the Jubilee and the Campy dropout. I did have to a drill and thread a hole in the dropout perpendicular to the derailleur bolt hole to accept a setscrew. The setscrew was necessary since the Jubilee's mounting bolt relied on a locknut on the rear of the mounting plate to secure the bolt. Mounting it to a Campy drop didn't allow enough thread on the backside to install a locknut, hence the need for a set screw to lock the derailleur bolt in place. I didn't have to do any grinding on the dropout or derailleur to get the correct angle. Granted, this was 25 years ago, but I don't think my memory is completely shot...
Kevin