The old articulation scout helmet upgraded to be compatible with newer figures. Originally the hole was too far in the helmet and the neck peg only just reached it, so there wasn't a lot of mobility. I then took a helmet that was already cut down into a stump I had intended to use on an old custom figure, hollowed out a hole in the scout helmet with my dremel, and glued the two parts together. A thin layer of epoxy was added to make it a bit more durable and to look smoother. I think that with a bit of sculpting, this could be applied to many of the old helmets like CQB, EVA, etc.