Fiberglass Sub Box Question

Instead of a Retangle plain jane box, I want to add some curves to it and give it a nice perl black finish. But I need some answers to get me on that way. I was wondering If I can build somewhat of a box. Side panels, Back, Bottom ( Leave the top and front open for the rings and a Amp rack ) and Build my fiberglass box off of that. Here is a page that sort of shows you what I want to build. (Note: I am using 2 12's and I want the amp rack before the speakers ) here is the page Baiscly I was wonder if I can use 3/4" Thick MDF as a frame and build off of it. Because I want a box that I can remove somewhat easly ( I am designing the box in with security in mind. the last box I made [MDF] had 15 break in attemps and the box could not be remove by them ) for camping trips. Any help would sure be appreciated. thanks

yes .....thats what he did in the blazer. the sides and bottom are all mdf. then they made the rings and a box for the amp. then stretched their mold fabric over it all and glassed away. i don't know what exactly they did cuz i don't know them but judging by the shape and what i can see in the pics, thats what it looks like they did.