I would be happy to help you and I have a couple of options for you depending on the dimensions of your recessed ball. The first option and the one I would strongly recommend is the Demco Recon Gooseneck-to-5th Wheel Trailer Hitch Adapter for Recessed Ball item # DM8550046 will fit a recessed ball mount if the ball sits no lower than 13/16" from the top of the bed. It has a gross towing weight of 21,000 lbs and a vertical load limit of 5,250 lbs.
The other option is the Ranch Hitch Universal... view full answer...
It is likely the correct fix yes, and the replacement cable actuated waste valve you need is the LaSalle Bristol Cable-Actuated RV Waste Valve for Black Water Tank - Spigot to Hub - 36" Cable # 34466N4AB36GM, 48" Cable # 34466N4AB48GMA, or 72" Cable # 34466N4AB72GMA.
To install it use LaSalle Bristol ABS Solvent Cement # 3447530889. view full answer...