You do need the billet cover as people have broken the standard ones as they weren’t designed to carry the diff on the cover. . MT and MK make covers. Either use the MK fitting kit or have your rear hoop modified to take the diff without the fitting kit. I used both and loved the simplicity of the modded beam to take the diff and you can 6 degree it at the same time for a big handling and traction improvement. If not use the fitting kit and it is plug and play.