I would never embark on such a project. Far too invasive, far too difficult and also probably far to expensive. The obvious solution (at least to me) would be a luggage rackon top of the spare wheel, with storage for a sidescreen bag. This is what most people are using, functional and low-tech, but not exactly cheap either. There are various providers, and when yout car is from 2014, it should be easy to find one. There are several models however, depending on if your car has full bumpers, overriders or no bumpers. I suppose you already are aware of the possibility of storing the screens (with or without the bag) on the luggage shelf behind the seats. Just enough space.
