I wish I had some pictures, or even a memory - but before I joined here and knew it couldn't be done - I installed a NR RD onto my Gitane TdF. Now the hanger had been threaded, but I don't recall any other modification, and I don't recall having any issues. I drilled the rear of the dropouts for adjustment screws and installed those as well. Obviously something else was going on - maybe the RD had been modded?