amp rack raised floor/recessed amps , acc

The car is a 2012 Mazda 6. Ideally I wanted to build the amp rack so that essentially, it would look like a one piece false bottom with recessed amps under plexiglass access panels with fans and vents. The enclosure would be rear facing and the rack be tightly fitted ad round it. A couple design issues I'm hoping to get advice on: The widest point on the trunk floor is 59". The trunk opening is only 44" . Of course this is common. On past cars, I've dealt by making the amp rack just a vinyled board that fits the length of the trunk, but id cut the width so that in the end its missing the 'wings' that would flare out around the wheels towards the rear. Never liked that because the corners of the real floor are exposed. For a design like the one I'm attempting, how do people make the rack fill the whole floor? Also, I'd like to maintain access to the spare. So screwing the rack down is something I'd like to avoid. I've searched around for info on this particular issue with little success or direct advice. Any help would be appreciated.

you have to make it in multiple pieces so and make them fit together like a single piece. take the trunk floor liner out and cut the exact shape out in whatever wood you plan to use. once you have that you need to find the best spots to cut it so that it will not look obvious that it is more than one piece, for example you can cut the wings off and treat them like side panels to hide the gaps in the corners. once the pieces are finished and carpeted it will be hard to notice the seam. or you can carpet the top with a single piece of carpet and then it would be held together as one piece but the sides would fold up to let you fit it where it needs to go.

If I do that... Will the flexible wings be vibrating?   The trunk's been deadened...

the sturdiness depends on the substructure you create to make the false floor space for your amps to live in. this folding panel is only a beauty cover for the amp rack underneath. if you build support under the seams and at the edges then no it wont flex or rattle. for extra strength you can glue velcro to the under side and make it stay where you want it to and you dont have to worry about shifting.