Viewing the Custom Attributes would be the best way to see the information from the additional stack members. You can set the asset tag field for the stack 'entity' itself, but you cannot assign it for the individual members of the stack. To set this select the General tab and fill in the Asset Tag field. Click the Save button. You will get a failure to write to device error (this would work for an N/S/K). For the stacks this will be stored in NetSight and is not written to the switch. You will also not see the asset tag in Custom Attributes as we read the following OID from the switch to populate that field: entPhysicalAssetID=1.3.6.1.2.1.47.1.1.1.1.15