I too suggest the 4.30 gearing. Traveled with a friend with a TT, under 8,000. He had a 6.2 F250 with the 3.73 gears. After a couple hours we agreed I'd follow him. He just wasn't able to keep up to me. Despite the heavier and high profile 5th our 6.7 diesel just plain outran him on every incline. Plus, he was really tired of the shifting after over 5k miles.
FWIW he has since traded and drives a '17 6.7 and after almost a year still has a huge smile.
Would I buy a 6.2 gasser – quite possibly, with the right gearing.