The 2 buttons are part of what is holding it in place. I think lots of trim needs taken out before you can get at the real fixings. The boot side liners, the rear pillars all need to come out first. Not sure how to deal with the airbag in the pillars. There are videos online for the saloon but I’ve yet to find one for the coupe. They’re quite different. The saloon is more of a cover where as mine has the whole rear brake light assembly and the Harmon Kardon speaker system all built in. I just need access to stick some soft Velcro strip along the window between the brake light housing and the window. But can’t get at it. If the speaker grille would pop off I could check the integrity of the speaker itself but it’s not coming off easy and I’m afraid of breaking clips. I thought there were You tube how too’s for everything these days. But not this apparently.