TTs are so aerodynamically poor that a molded cap isn't really going to help, and I doubt the V-nose ones help, either. I don't think the cap goes over a standard front cap, but I honestly don't know. My new one has it too, but I'm not sure you could tell by looking.
Jack and Delores, Weatherford, Texas
2016 White Hawk 28DSBH TT, 2014 Ram 4X4 2500 CTD