What I would do is this.
Place the profile along the front and wrap around the end (horizontally) - both profiles in the same layer so they trim automatically.
Place the raking beam on the side in a different layer with a different layer intersection priority number so it won't trim automatically.
In an elevation from the end determine the intersection angle or the roof and horizontal profiles.
Place a zero thickness roof at this angle from the top back edge of your profile.
SEO the horizontal profile to this roof with downward extrusion and SEO the sloping profile to this roof with upward extrusion.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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