Whether it will be obvious to readers - depends how good a writer you are, doesn't it?!
Given the wonderfulness of the internet, I think it might be possible for you to find someone who has been there or knows it well to beta read your completed draft for you. You will have to return the favour but I bet there are people who know Mexico and want to set books in England and would appreciate you checking through theirs for them. If you join a big, America-based forum like AbsoluteWrite.com you will probably be able to hunt someone down. If you start networking now you'll have plenty of contacts lined up by the time you finish.
I recently read a book set in Tudor England, written by an American author, which had chipmunks running around in it. Would have been SO easy to prevent that