I just installed 2 15" MTX 5000 Subwoofers with a Crunch V-6004 that gives them 1200 watts and all you can hear outside is rattles and if you turn it really up you can even hear it inside. The rattling in the trunk is mostly on the sides of the trunk. If anyone could tell me what to bolt down really tight or what is the cheapest sound deadening material because I am really short on cash right now. Thanks