Hi there. There is a way to do this, though you will no longer be able to use the original part file (or import another part with the same name). You can follow the steps below to replace the part with an assembly on the item in question.
1. Navigate to the BOM view of the project where you have the item saved in the web.
2. Right click the item and select "New Version"
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3. There will be a warning message telling you that the CAD file will be disassociated from the item in this new version. Select Continue.
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4. Open the assembly you wish to associate to the item in Solidworks.
5. Login to the Upchain CAD plugin in and navigate to the item in the project BOM that we just removed the CAD file from.
6. Right click on the item in question and select "Attach Active CAD file"
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7. Switch to the cBOM view and refresh. You should see the assembly attached to the item with any children of the assembly brought in as phantom parts. You can create items for those phantom parts if necessary by checking them out and selecting "Create Item"
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