Yes, you can use the Curt CrossWing Lightweight Gooseneck-to-5th-Wheel Trailer Hitch Adapter # C32DR with your 2021 F-350. However, it is possible you will not be able to make a full 90 degree turn since you have the short bed, so that is something you need to be aware of. If you have a 5th wheel with a tapered nose it is unlikely clearance will be a problem. view full answer...