I just purchased a 2015 Vantage Roadster about 4 months ago and have learned a ton from posts on this forum so thank you!
My car had cracks in all four corners of the piano black veneer of the waterfall so I changed it out yesterday. I thought I would post some photos since I had trouble finding any when I was researching it before starting.
Since the veneer was already cracked, I elected to use the "yank like hell" method of loosening the waterfall from the 4 clip holes rather than trying to pry it out.




Once it was loose, I lifted it from the rear and propped it up with a piece of wood while I disconnected the 4 plug in connections





Next I lowered the waterfall and removed 2 Phillips head screws that hold a fabric safety strap just below the speaker grill.





With the whole assembly now on the work bench remove the four Torx head screws attaching the Nav assembly to the waterfall.




Remove the 2 screws to the opening mechanism.





Remove the mechanism and the spring underneath.





Remove two Torx head screws holding the Nav cover and unplug the Nav screen





Remove the C clip from the screen



Remove the screen and attached cover out of the Nav assembly. Gently lift the screen surround from the end that the screws were removed from earlier and and slide it up and over the screen.
(The new Nav screen cover is laying on the towel in the background)




The screen surround is secured at the other end by two flat prongs




Lift the the screen and its circuit board straight up and out




Now the other Nav cover screws are accessible.





Hope this helps someone in the future.
Bill

 

You are three weeks too late. I just did the same procedure on my 2015 last month. I too was frustrated as prior instructions did not apply to newer nav. I took different approach in not taking ends off of nav mechanism. You can actually slide the nav screen out of the carrier but kind of finicky. I think I like you approach better. Had a minor stroke after reassembly when nav would not rotate but later found out drive motor connector was not locked in place. All I could imagine was I broke my motor or gears. Final product was very gratifying. Thanks for posting.