A direct link helps: http://eaacorp.com/wp-content/uploads/2012/10/Safety-Upgrade-Notice.pdf
Anyway, I believe you'll find that most here are perfectly capable of taking their own firing pin out, noting the orientation, and then putting it back in again. If you just want to send in the FP to get the new one and perform your own installation, maybe just call EAA and see if they're fine with that.