That's exactly what I did right after I mentioned that I needed more tiles. I am now working three tiles below the, ahem, Andes and you're correct, got a 6/2 plus a 4/2 and 3/2, if I recall. Andes is now growing well.
Cusco, on the other hand, is barely hanging in there as it spends most of the time building the critical cultural wonders (Sistine, now Uffizi, then PT and Hermitage). Having to put more into hammers instead of food (in a race with Persia now for Uffizi) but have not built any of the hammer buildings yet (those were the 1-2 turns techs I'm currently doing now that I got Acoustics and Architecture).