Wow, this thread is still raging on!

To answer the big question: The disc was all plastic.

How did I get it off? Believe it or not, scissors worked better then shears. Then on another bike I tried the hot paper-clip method, except I could only find bobby-pins, so I broke those in half and used them. I wonder if paper-clips retain their heat better then bobby-pins, because I had to reheat mine quite often during the operation. Anyways, took about the same amount of time, but the hot-bobby-pin method was way more fun - all guys are pyros on the inside...