I attempted to do my 66 but ran into an issue. There is a pinchweld near the tope of the door under the wing window that would have to be removed in order for glass to be able to go up and down. Once that weld is broken, the door skin etc. loses it's rigidity and throws all kinds of alignment and strength out the window. I tried it on a spare door just for grins and gave up.
I know one of the other guys on here did it with a 65 I believe but think it was a post car. I also saw one out of Denver that was done but they put a modern day mirror where the wing window was and it didn't look quite right. I'm not saying it can't be done but I didn't figure it out and had several others look at it too. I'd hate to see you ruin a door by cutting it and not be able to get it done either. I would recommend trying it on a scrap door and see if you can get it.
The car in the picture almost looks like one of the Venom fiberglass cars which I know has the wing windows gone.
Good luck on the project.