Membership 2 Pro - subscription completed auto email - add "first name"?

I'm trying to figure out how to add a user's first name to the automated email sent upon completion of signing up.
%username% is replaced with the user's username (obviously?)
...but I haven't been able to get other variations of the user's info -- I've tried:
%firstname%
%first_name%
%name%
%fullname%

I've tried searching for this info, but came up empty. I'm assuming it must be possible (how could it not be?)... so, what do I need to put in the email to get the user's name?

Thanks,
Scott

-edit-
Ok, I feel stupid... I was using the "text" editor where there's no editor button for the membership fields... I switched over to the visual editor (which I almost never use) and there it was!