Muppetlab: I attached wires to the bottoms of her eyeballs, then poked them right through her head and twisted them together on the inside. Then I bent them back and covered the ends with the foam padding that I insert to keep my hand from rattling around inside the head.
muppetperson: Thank you! That "ridge" is a seam that was imperfectly brushed down. Now that I use the baseball stitch on the heads I no longer have raised ridges to deal with, but hiding seams is still a pain-in-the-neck task, and the wrong lighting can make an imperfectly picked & brushed seam into a Frankenstein scar!
If you watch the original series carefully you can see some seams and ridges on the puppets. The most obvious one runs down the middle of Large Marvin's snout. I also often see seams around wrists and ankles, and when characters look up sometimes between the neck and head. Somehow spotting those makes me feel a little better about my own puppets' imperfections.