Just wanted to put this up so I could find it later. This is an armature that Justin Connolly learned how to make from Seamus and Robin Walsh at screen novelties. (here's his post with full description) Brilliantly clean and clear replaceable limb system.
And this is the amazing Josh and Nathan's Flynns' replacement face stuff, definitely a fantastic resource. Interesting to see how they cast an imcomplete head, then completed the individual ones with sculpey.