Problem with modelling a differing radius

Hi!

I’m having trouble with modelling a solid piece, which is a saddle like seat. The problem for me is how to do a differing radius fillet around the piece. I’ve check a lot of videos, and what I’ve learned so far is that filleting probably won’t be the option to go for. How about Loft of SrfNetwork?

I’m new to the channel so correct my etiquette around the forum if needed.

is a model that the seat it’s based of.

Sadde_seat.3dm and here is a 3D model with current measures.

Thanks!
Joel

I’d break this up into manageable surfaces. That can point edited and trim where needed. This method will produce the best result. It does require advanced surfacing skills.