Can't we all just get along. Look at how many parts a car has? Anything can go wrong with a car. If anything I'd say aftermarket bolt-ons are the healthiest thing for a car if its maintained and tuned. Give the guy a break. +5 Wish I was rich I'd snatch this. Good luck with sale.
Battery Suggestions? Stock battery is a POS for sure. It died and gone, need a new one ASAP. Looking for cheap and cost effective, battery got a system too. Looking at Costco's Kirkland or Duralast Gold?
Possibly, you may be able to get the filter off by taking off the driver side fender well. It's not a guarantee, because its tight and depending on the way your clamp is set on. I really can't think of any other way.