Couple hours drive later, I finally got the car home.
After a quick rinse it looks like this. I am aware that there are shared opinions with regards to the way the car looks with the Jehle modifications, but I think it looks fantastic. Though I've always loved an oddball.
I have conversed a little bit with Mr. Jehle himself after acquiring the car (through e-mail and via a few facebook-group members), and he could enlighten me on some of the changes he made to it.
It seems he completely restored the chassis of the vehicle, and replaced all rusty sheet metal. He then re-created the whole bodywork (except roof) in fibreglass. Doors, hood, fenders, rear end - all fibreglass. And as you can see, the trunk lid is made from aluminium. The latter might be stock, but having never seen an original Deauville, I have nothing to compare with.
The new fibreglass body is wider at the front and rear. The change is more discreet in the front, while the rear is based on the Jehle Longchamp flares.
He also found the moulds for the body in his workshop. Still hoping he will find som papers on the car in his archives / office.