The rework of the access door gap worked out much better this time. After sanding the area smooth, I moved on to the upper cowl fasteners.
Both cowl halves were remounted on the plane, and the mounting holes for the upper cowl were updrilled to #20. Rivet holes for the anchor nuts were drilled in all of the mounting flanges, and then countersunk for 3/32” solid rivets. The screw holes in the upper aluminum flange were dimpled, and the screw holes in the horizontal fiberglass flanges on the lower cowling were countersunk.
The anchor nuts were riveted in place, but apparently I have forgotten how to count, because I ended up being nine short. Aggravating!
The upper cowling was screwed in place, and generally looks good. Some minor tweaking will be required in a few areas before I will be content.
