Nate, this is what we used for Thunderhill earlier this year. The trailer is a 20' and doable but you end up running out of room after the track supplies are loaded.
The truck, no issues. Super comfortable, quiet and would pull any hill from Seattle at 70+. I'd look down and realize I was doing 85, never felt like the truck was working. The bad, even on the flats of Northern Cali we couldn't get any better than 9.5mpg. Hackster was laughing at us as he was pulling his truck down on an open trailer with his older Cummins knocking down 16-17mpg.