I’m a bit stuck modeling this. If the mount was just 90 degrees, I’d be able to do it, but having the pole be mounted at an angle and trying to do a concave shape stumps me.
How much detail does it need to have? How will you be using the resulting component?
Its just to mount an angled sign post on my model of a building. It doesn’t need to be super detailed, but I would like to get the concave transition to the wall.
I would start with the back plate and the tube in place. I would copy the ellipse where the tube meets the back plate and use Offset to create a larger ellipse to define the limit of the fillet on the plate. I placed a face at an angle through the tube where I wanted the other limit of the fillet and used Intersect Faces with Model to get that ellipse. Then I connected them with curves at the 12:00, 3:00, and 6:00 positions. Shown in blue, below. I used Curviloft to create the surface, shown in yellow. Made a flipped copy, exploded them and then joied all the geometry together softening edges as needed.
I don’t know how much experience and skill you have in SketchUp. If you need more detail, let me know.