it would be much better to take out the stock rear deck and build a new one out of wood wrap it in nice carpet cut a hole for where the med kit existed and drop a 8inch FREE AIR sub it must be a free air and then run a mono amp you dotn need a huge sub in the trunk to rattel the hell out of your car if you want sound proofing screw that dyno matt crap its BS go to Home Depot and ask for Quick Roof its the same stuff and absorbs sound jsut as good i used it on my car its amazing and i dont mess around good luck