Decided to install a hinge on the bottom of the left wingtip that will hopefully be somewhat more secure than the right. Used my rivet fan to lay out holes in between the ones already in the bottom of the wing. Match drilled the wider -4 half of the hinge to the wing, then drilled out the additional holes once the hinge half was secure with clecoes. Removed the hinge half and installed it into the left bottom wingtip and match drilled the additional holes to the wingtip. Marked the centerline of the narrower -3 hinge half and used the -4 hinge half once again to mark the -3 half for rivet holes.