Finished riveting the skins to the forward spar. Noticed one loose rivet on one of the nose ribs. The rib had been covered over by the front spar so access was difficult. I taped the bucking bar to a chisel and held it in place between a lightening hole while Marlene ran the rivet gun. It worked! No more loose rivet. I will ask Van's what builders or flyers do when they have encountered a loose rivet in a location they cannot place a bucking bar.