Post your quarter mile times.

[BlackSTX]

I can't recall the speed, but I ran 16.9 with my '05 Supercab with 4.6L. I have an AEM CAI, and a SI/DO Magnaflow system with a couple of tunes by Bill. I did my run on the 93 octane setting on an 80-something degree day.
I also did a run this past winter with the same power level but on a 26 degree day and shaved a full second off the time.

Sure, you can get more, but that is equally related to how much money you want to spend. I don't expect you're likely to get much more out of your truck unless you start changing some internal parts like cams, heads, add a supercharger, and so on. Tuning is only going to take you so far; you're optimizing the parameters for the components you're using, and there's only so much you can do without changing more of those components. Unfortunately, gas engines are as responsive to tuning as diesels.