Does anyone have any idea on how or why I can't edit this thickness included in the on-line tutorial as seen on the attachments?
Because it is drawn in solidworks as a sheetmetal part. The thickness is automatically taken from the sheetmetal input in your solidworks tree.
So if you want to edit it: go to the SW tree and select the part in the assembly. There you can edit the sheetmetal properties.
Like most questions in SW, the answer makes since once you see it;)
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