Modification necessary
"The frame mount bracket is designed for a C-channel frame. The 2018 superduty has a fully boxed frame which means there is no way to attach the frame bracket that comes with the kit (no way to get hardware or wrench on inside of frame) . Contacted longhorn fab directly to see if they a different bracket available, but have had no luck so far. Went with this kit for the bolt on option but it seems as though welding will be required."