I've never been but I'd make sure I had some shrimp flies tyed w/ tan rabbit strips. Rabbit fur strips have been the most lucky for me. What my Mexico guide likes to do for permit is have on a larger shrimp pattern that will catch bones but also catch permit. He likes shrimp flies for permit b/c you actually strip the fly and where a crab fly has to be motion less. Less guess work if the permit ate the crab or not.
Just something to think about.
megalops atlanticus lover