Converting a Nuovo or Super Record derailleur to a long cage "Rally" version is quite simple as other list members have pointed out.
Here's a photo of a Super Record that I converted that was originally mounted to my Rauler "Day Tourer":
http://www.wooljersey.com/
This bike now sports a first generation series Rally derailleur that was not correctly pivoting at the upper sprung mounting bolt (I posted this last week on the list). When the upper mounting bolt was properly tightened to the dropout hanger, the derailleur would not pivot as intended. I had the exact same problem with an identical Rally that was mounted on my Rauler tandem.
I finally fixed the problem(s) by removing the upper mounting bolt and spring, and lightly filing the inside edge of the bolt body barrel. This was my initial thought solution to problem, and it worked perfectly, with both derailleurs now working perfectly!!! Suspect the factory mis-cast these upper bodies barrel a bit too wide, or there was excessive plating to this area (yes, these Rally derailleurs were plated over the alloy bodies).
Sorry for the joke posted about scrapping them - no, they were not thrown into the recycle bin for future aluminum soda/beer can production!
Regards,
Kevin Kruger - Grantville, PA