Help!!! I have a 05 CTD 4x4 and I can't decide which box to get. I tow a 8000lb TT in the mountians of WV so I want to be tow safe. And it is a daily driver. I want a little more bottom end snap and better throttle responce and maybe some more mpg's. Gosh there are so many choices I don't know which way to go . Thanks