I have taped over the rivet lines of the bottom fuel tank stiffeners using riveting tape. I assume that the sealant applied to the surface of the stiffeners will squish out enough to seal out the rivet holes. The rivet heads turned out quite nicely except for one stiffener where I’ll have to remove most of the rivets and reinstall them.
AN426AD3-3.5 rivets bathing in Acetone prior to installation
