The mechanisms are quite heavy as well. Normally I think a CF roof would be hard to replace but not with these cars, that is if you can get the glass off easily enough.
The welds will be under the glass/rubber trim around the edges, have to pull the windshield and maybe the rear window, I guess that is a bit of a hassle as well. But, maybe not with this design we have.
If the windows can be left in place, just pull down the headliner, unbolt everything you can and remove it, drill out some spot welds, remove the whole thing, glue? the new roof in place, I am talking the whole roof in one piece, no longer opening. Then make some trim panels for the holes inside and you are done.
This would result in a huge savings of weight that is currently located ina terrible place for handling dynamics.
Of course tires, wheels, suspension mods etc can compensate to a very high degree, removing it entirely would be far better yet.
I will do this if one comes out, if not, maybe next year, I may just build my own!!