Creating mates on a cone

Colm_Rev

Could someone tell me how I would mate the long yellow plate to the outside of the hopper/cone.
I made a sketch in the part studio of the cone, can this sketch be made visible in the assembly

Thanks
Colm

emagdalenaC2i

Could you share your document, so we can explain it better?

But maybe you can use an offset in the mate connector... 
https://www.youtube.com/watch?v=kK79nwi62Bg&t=87s