What to do with this hatchback trunk?

The speaker box is going to go, the sub will move to the corner of the trunk (not in the spare tire area) in a glass enclosure.

I was thinking of putting masking tape down, after I removed the carpet, and connecting the sides of the spare well with the sides of the battery box. I would then lay down some glass on top of that, and when that piece cured, I would stretch some cloth across the top of that and resin it. Then add plenty of layers for strength, and cut the battery box hole through that layer (using the bottom layer as a guide).

Does that make sense? Then I would carpet it all and all you would see would be the speaker in one corner, a  flat floor, and the top of the battery box sticking out of the middle of it all. I also plan on covering or painting the battery box.

Any better/more reasonable ideas of what I should do and how to do it? I've already moved the battery box to the spare well so I am set on working around that but I am open to suggestions on everything else.

Also for people who do race the battery over the tire gives you more traction for rear wheel drive cars. Because it puts more weight over that tire, its kindof like putting a very small person over your tire. hehe!   

Alright kosoku why not just hot glue some fleece to the box like you want it and then to the sides around the spare tire well. Then resin that and build it from there. Make sure you put the tape down around it and you should be able to remove it like you said before. The hot glue will come loose. Make sure you have some kind of vent hidden some where so the amp can get fresh air to it w/ the help of the fan of course. this may not matter but I figure it should extend your amps life. I would definately paint the box that acid from the battery is probably not going to work real well on carpet, I would paint it like a flat black.  any more questions let us know

Thats just my opinions though.