Hey guys can you help me get this straight. I am reading that stock fuel pumps are failing and it best to replace with FASS or Air Dog ect. Here is my question, my current ride is a 2003 dually 48re 4:10s 4x4 sport pkg. 38,000 miles. Which pump gets replaced? Is it behind the stock fuel filter? If you install the FASS on the frame rail is the rest of the install difficult? I just put in a Amsoil duel bypass filter and to me it was not to hard to do. Does the stock fuel filter stay? I have heard some buzz about in tank pumps? I have a blank slate and would like to get to work on my truck. Your help is appreciated , also In order to stay in the sweet spot on the high way I need to drive at 58 mph, my thoughts were to put in a gear venders over drive ? Is this idea solid or would taller tires be a valid option? stock tires are 235/80/17 I dont know what would be a good size.