Apologies, im fairly new to using the smart fasteners (should have been using this feature before now). The picute shows two sheel metla parts. The grey one has a hole which goes through both side flanges. I click on the surface of the green plate to generate the smart fastener, when I go to add a washer and nut to the bolt, it is shown on the opposite flange. I need the nut on the 'inside of the box'.