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How do I delete merging faces that come from multiple planes?
Thank you Vladimir, I will try that
I agree that if these had been created as a Weldment part the process would be easier, but since you've got what you've got, you should be able to use the Indent feature to use one body to cut another, then the Delete Body feature to remove any remaining unwanted remnants.
Try to reset bodies as weldments structure members and use Trim/Extend tools available for Weldments only.