A while back I sold the whole top for a 30-31 coupe. I had it on the HAMB and nobody wanted the whole thing so I sold it piece by piece and got almost a grand for it.
That's what it would take, a complete donor roof. I've seen people make roadsters out of them, but can't remember anyone making a coupe. Shouldn't be terribly hard if you get enough of a coupe roof though.