Research ball mounts at eTrailer.com and look at the adjustable units. I prefer the aluminum adjustable with the dial gauge so you can monitor the correct weight on your tounge. Make sure to choose the appropriate receiver size (2", 2 1/2", or 3" if you have a 2017+ Superduty) when you order.
2017 F350 Dually 6.7
He who dies with the most tools, wins!