I just got offline with AM Chat Support, who was able to put my wife and I (I'm PM, she's Silver) in F on our GDL->LAX leg. So hopefully that won't be a problem for you.
Which brings the next question - the chat support rep said that I should arrive at GDL 3 hours ahead of my departure. Is that an accurate assessment? Do they have an Elite Plus checkin desk that might save me time?