I've just installed a amp and sub in my trunk and I have a fair amount of light dim. I've got a Alpine MRP-M450 and a JL 10" running at 2 ohm and I'm thinking that perhaps I need to find a better ground. I hooked into a grounding screw on the drivers side of the trunk near the fuel pump reset switch. Anyone else have anything that might work better or could it be something else entirely.