replaced the 18" wheels and tires on their newer 2500 truck with 16" to get away from height and fifth wheel clearance issues. Don't know why the new trucks are so tall but my newer (2015) is 58" tal...
Do you already have a 5th wheel? Reason I ask is that it's not that big of a deal most of the time. I've pulled the same mid profile 5er with two 2500 trucks. A 2012 and a 2018. 5er sat about 1" high in the front with 6+" of clearance. Bed height at the tailgate is 59.5"