I done what u said..that is 3/4 MDF.. friend built for me ..no carpet..but here is a pic of my trunk.


I used the oem trunk carpet and used some industrial staples to secure it on my box...Underneath the amp is a board of MDF the lenght of the trunk and the width of the space left..from the back of the box to end of my trunk. I noticed when i would accelerate quickly my box would slide and hit my amp..so i got a board of mdf and stuck it in between flush so now it wedges / stops the box from moving..n heck this pick is old i cut a whole n all the wires are underneath the carp..next thing is prob buildin a box to go were the spare goes lol ..but yea i done tried what u want..it works..but if u have a moon/sun roof....be careful...I "derailed" mine..or so says the local body shop..I need a new moonroof n its about 1k ...lol..


hope that helps