Louise, just not to leave this item pending.  You asked me to talk to Steve and think about a differen ttitle...After hours of deliberation, I propose to you that we keep the regular US title  (Director), and we avoid any confusion. In terms of our customers I'll just tell them I am director for the Monterrey office.
Let me know if you are OK so I can immediately correct my business cards. 
Thanks and have agood weekend.