I think '67 fenders for any model Chrysler will also work, but they won't have the side vents. Are you also planning on updating the rear of the car? I'm amazed and impressed by the transformation of this car.
The tonneau cover is supposed to have a rubber strip that slides into that groove. It's a bugger to get it in there. My feeling is that the designers intended it to be semi-permanently installed and the cover stored in the well when the top is up. I don't do that because my cover is white and...