I have a K&N drop in filter for sale. It is #33-2135 out of my 03 2500HD w/6.0L. Does fit other years and model but check with www.knfilters.com for applications. It only has 186 mi on it so it is basically brand new. Two days after buying it I got a deal on a K&N FIPK and bought and installed it. Paid $60 couple weeks ago and will sell it for $45 shipped.