Abstract: A method includes drilling a first aperture in a panel that extends between a panel first surface and a panel second surface. The first aperture projects into the panel along a first centerline from the panel first surface. The first centerline is angularly offset from the panel first surface by a first angle. A first tool is arranged with the panel. The first tool includes a support structure, a locator and a drill guide. The locator is mounted to the support structure and projects into the first aperture. The drill guide is mounted to the support structure and is arranged adjacent the panel second surface. A second aperture is drilled in the panel using the drill guide. The second aperture projects into the panel along a second centerline from the panel second surface to the first aperture. The second centerline is coaxial with the first centerline.