It seems Fusion 360 has an issue trimming parts of a patch that is inside the model.
I used different display modes but no mode highlight the parts correctly I wanted to remove.
It would be great in that instance for example if Fusion can give you the option to either remove or keep what you select as well.
So in this case I select the wheel rim design as the cutting tool, select the wheel outside and decide to keep that one so Fusion cuts the overlap inside the model.

Here is a cross section view showing the fine thin strip overhangs inside the model.

I could use the split tool but with a geometry like this the amount of steps I would have to do is too much to expect.
Also as a side note because the zoom issue not being able to get very close the mouse has issues also even selecting the geometry I just split. And unstitching an object with 246 patches just to remove those strips will be painfull 😉
