I must have shaped the ribs on the starboard wing incorrectly, because the sheeting on the top of the wing was recessed from the original sheeting. At first I figured I could fill it with the Model Lite but an experiment showed it would be way too much filler. So, I went with a different approach.
Once the glue cured, I taped up the surrounding sheeting to protect it. Thanks for the tip, Dave!
After a lot of sanding, the new section of the wing is flush with the old.