Thank you all for the great inputs!
After thinking a little more about this I am not sure that I would be able to cut it while it is curved because of the available tools and the risk of working with the big pieces upright. But I think that this was a really inspiring discussion, so thanks for that!
What I see as my possibilities now are the following two scenarios:
1: I ‘redesign’ the hood pieces so that they will not have a 45 degree miter, but instead just ‘flat’ edges. Then I will make the two side pieces a little shorter and let the face piece lean against them. I will assemble the two side pieces first, hold the face piece in place, scribe where they meet and then lay the face piece flat and cut it. That would require some sanding and filling, but do you think that approach would work or is there something with the curves that I have not thought of?
2: I try to find someone with a CNC router to cut it for me.
But with that approach I have the following questions:
2.1: How do I export a ‘3d’ file that can be used with a cnc?
If I export to DXF I will just get a ‘flat’ file with the shapes, but I guess I would need a ‘3D’ file to also show the miter.
2.2: How do I lay the piece flat in 3D? I can use the "unwrap and flatten faces’ plugin, and that works great if I only select one face. But how to flatten the pieces when I also need to show the bevel?
Or is it not even necessary to flatten it if I want to create a file for a CNC?
Thanks for all your great inputs!
PS - should question 2 be a separate topic?