You have to measure. Every truck is going to be slightly different depending on tire inflation pressure, tread depth, roof rack style, actually height you set the coils to, how much weight in the vehicle etc.
My bone stock Pro is 78" (6'6") but a good portion of that is the rack. My garage at work is 79" so it's close and actually hits the height limit pole on some days depending on how fast I'm going and if I'm closer to the left or right side when I go under
Before I can do anything to the truck at all, including tires, I'm going to have to swap out that Pro roof rack for something much more low profile.