I have a fairly large 3 cubic foot box with 2 10" type-rs in it and this thing weights a hefty amount. but the **** thing keeps sliding around in my trunk and the on the one side it keeps ripping the cords out of the terminals on the back. I know this partially due to the fact that i didnt carpet the box yet cause i was to ansty to finish cause of leaving for school. But once i get it carpeted what is a good way to keep that thing PLANTED so i can still have some fun without hearing a huge *** thud in the trunk?????