There's a million way to skin a
Crow cat... here's one way!
You make reference to the little "gap" when Crow's mouth is closed... that happens because the sides of the pin can get "compressed" slightly.. causing the bottom of the beak to be narrower than the other half... that extra plastic has to move somewhere, so you end up with a little gappiness since the bottom jaw is now narrower, and making it slightly longer. (It's always the bottom that contracts slightly... since the Crown or E gives the top a tiny bit more rigidity).

Gapping happens all over... notice the back of the jaw is slightly off (till I adjusted it).

Here's the interior of Crow's mouth... the hinge is a piece of boot weight leather with plastic screws securing it... good for 100 trillion operations. Your arm will break before the leather will.

Notice the not very noticeable screw holding it all in place. You can't really see it, but there is a corresponding screw on the other side of the hinge. What I used were plastic fastener type screws that you'd see in automobiles (they paint well). Lowes has them in those giant "junk drawers" over by their regular screw section.
