Per husky hitch manual:
Verify that the cross member is set at the proper height to provide a minimum of 6" clearance between the bottom of the trailer nose (pin box) and the top of the truck bedsides, and allows for a level-towing attitude of the 5th Wheel Trailer
At a minimum this should be 6”, if the trailer and tow vehicle are going off-road then this needs to be 8” to 10”.
Pin box design can be an issue too - was on a Montana I had. The back of the pin box was square - I had to cut off some to make an angle on the back so it would not hit the box of the truck. I did not know it was a problem until I took a sharp turn and put a dent in the side rail of my truck. Filled it in with RTV - painted with touch up paint and covered the bed rails with Bushwacker bed rail caps
Problem found when I went from a 2005 to 2011 chevy - box is about 3 inches higher on the 2007 and newer models.
My present trailer pin box is angled on the back.

