I have fitted the proper towbar & an upgraded valance for an sline, as mines detachable, you can buy a valance that has a removable cover for the sport & slines trims level, when its in place its hardly noticeable mate & it was about £60, but requires painting.
Bumper of job to get to the fixings though, I had the sport upper so I modded the valanceit to fit given, was sline valance on sport upper which dont 100% plugnplay, but looks oem now, is yours a static tow or detach ball?
If detach then just swap valance over mate, always handy having tow hitch for say bikes etc.