I stumbled across this DIY cabrio this afternoon. From the first pic, taken at a distance I thought it was a Voll Cabrio. But the owner, Hamed T. has informed me that he converted it into a cabrio himself.
This was the first pic I saw.
Here are two more pics, in better focus. Notice the curve over the triangle window. You will see this same curve in the Lumma cabrios, whereas the Voll Cabrios by Baur have a different angle at that point. So I would say that this is definitely not a factory cabrio.
Nice job, Hamed! :)