OK so here is my delema, i have a 2004 F-150 super crew and i am trying to hook up 2 12' subwoofers under my back seat. i have the box and bench seat spacers already but the problem i have is if i am able to just buy a converter for the stock headunit or if i have to buy a new head unit. i know the 04' lariat supercrew had a upgraded sound package were subs came with it. so like i said my question is if i have to change headunits or if i can splice wires an get a converter. thanks for the help guys.