well I had some old stereo equipment laying around the garage so I said what the heck. I wanted to keep the head unit so I hooked up the line converter into the back heel board speaker wire bundle...ran the RcA plug to the trunk...installed a crossover for the low filter, hooked up the Ole School Punch 45 from 1985 and VIOLA it ran my sub just fine....just enough for the added bass the jag needs. The only thing is I don't think the POLK's are going to be able to handle the bass. I only bought two used ones to just see how I liked them. They have good highs and mids but the bass quality isn't all that to me. It won't handle anything really but a +2 on the head unit. Anything else and it rattles and distorts. Anyone have suggestions on better speakers to handle it? I will have to replace all as the rear Jag factory speakers are original and one rattles a lil now since its seal is busted.