Insets Along Curved/Tapered Surface

 From:  Skwerm
Hello, all! I'm a poly and CAD modeling veteran trying to come to grips with the elegant world of nurbs modeling.

I'm trying to model a street light pole that has a curved/tapered base imprinted with vertical grooves. I've attached a PDF showing the pole and base I'm trying to model as well as the meager beginnings of the base. As you can see in the 3DM, I've projected the outer shape of the inset groove to the surface of the base, but now I'm stuck with what to do next. I'm beginning to think I'm on the wrong track altogether.

If the base was a cylinder and wasn't curved/tapered I'd just make a cylinder with hemispherical end caps and boolean that out of the base. But the curved/tapered nature of the base's surface won't allow this workflow. So here I am; stuck.

I will appreciate any and all help with figuring out how best to do this.