I have a 2001 GMC Yukon XL 2500 with the big block 8.1 with only 137,000 miles on it. It has 9" on lift and 37's. The motor is stock, but a K&N cold air intake will be added this week. It's gonna be used as a tow and show rig. What can ya'll do for me and how much $$'s? I don't plan to do any other performance mods, wanna keep it reliable and easy to work on