Solid Trim

Hi everyone ;

I've sometimes some troubles understanding how GH is working, and it would be awesome if someone could help me.

I would like to perform a solid trim on two breps. The first one is a closed brep, whereas the second one is an untrimmed surface. Obviously, the Trim Solid component isn't working in this particular case. Can we transform the untrimmed surface (which is a closed ellipsoid) into a closed brep, or is there any other solution to perform this solid trim ?

Thanks a lot for your help !