Well done Neil, glad it turned out okay. Its obvious the card was for stiffening only, and the wire for shaping. I'll have to get my D Mask out and have a feel, but I'm sure the metal in my nose section is flat ribbon type.
Even though it was designed to be shaped around the nose (and the manual stresses that it was to be worn by the owner only whom it was shaped for) I was watching 'One of our Aircraft is Missing' a few days ago, and most of the crew are wearing their masks with the nose bridge down around their mouths! Definate oxy leakage!