Okay, I have gotten to the part in my mod where I am experimenting with the headanis (thank you for telling me about those mods, I found the anis there), however I am experiencing some odd behavior. I edited the messages.tbl to reference the various anis I wanted for the standard persona messages, but in mission the only anis that appear are the ones that I selected in FRED for messages written in the event editor, the random wingman messages (killed an enemy, more enemies arriving, accepting orders, etc.) don't have headanis.
This isn't necessarily a game breaker, in fact I might keep it this way since it's less crowded, but I would like to know why they aren't showing up.