Decided to make another access panel but this time have five fasteners instead of four. The ring is made from 6061-T6 .032 and the cover is 6061-T6 .025. The holes for the #6 screws are drilled to a #28. Dimpled all the holes. Added a piece of 1/8” heat shrink, Stein Air (SA702B), around the tail light wires where the wires will exit the rudder. This is also where the access panel will be.