If your located close to San Antonio then you could set up an appointment to go get it done. If you dont feel like driving there, you could fill out the online tune form and send it in. One of the members on here with a reg cab 4.8 just like yours dropped a full second JUST from nelsons tune. He was completely stock and the tune dropped him a full second in the 1/4. Here is the link http://www.nelsonperformance.com/tuning.htm

Have you thought about clearing out the yellow in your headlights? There is an easy/free mod you can do to your headlights to get the yellow out. It will look sick with the white if you cleared out your lenses.