Sorry that it took me a bit to reply to your last message. I enjoy the PHP programmer, its functionality and displays are great to have. I do not have any prior experience with SCT or VMP. Gryphon does adjust transmission shifts, at their rpm, and firmness. I am running an 87 octane tune. I ran a custom 93 in my old truck and it really woke it up performance wise, but it didn't make up for the mpg.The tuner will help get a couple mpgs but nothing drastically. Same for the cat-back plan, the muffler is the main restricted source, except on 09+ which have a straight through muffler. I am running the stock 3.73s on my truck. I feel it not necessary to change gears with small 33s, however, with larger and heavier 35s it would be worth a gear change.

On these 04-08 models, the 14" would be the biggest you would want to go. I do believe the 11" body is the best choice for these trucks without cat work and headers. My 11s were #11366.

When I had the 11" oval Magnaflows, it was real nice. Quiet inside on cruise, loud on acceleration, but faint silent at idle. The Bullets were obnoxious loud in every scenario. Droned badly on the highway, loud but deep toned down the road, my neighbor heard it every morning upon start up.

I do but my host pic site is currently down. I'll check again tomorrow

hey bud, im currently running a 2.5" dynomax bullet, stock cats and the stock tail pipe so 2.5" piping. i cut and welded the exhuast myself, if your going to get a shop to do it i would get the 3 inch bullet and 3 inch piping if you want it a tad bit louder than what mine is. let me know if you need more info and what you get done. lates bud!