I took on a challenge for a friend to try to create a pair of replacement parts for his 1999 Crestliner boat. He tried to purchase replacements, but they do not make the parts anymore. There were some tricky angles, but I was able to account for them with Shapr3D. The mirror command let me create the second part with just a few pen types.
Great job and I am sure you have impressed your friend.
Did you start the model by creating a solid first, then shelling it. If so, you can also replicate the rounded corners using the radius/chamfer technique before shelling. That way you can make it look exactly the same as the original part with only a few steps… Do not use Offset tool, as you may get sharper internal angles that way.