TRAVELING USA to Mexico

BOB the gcc is going charter with me to Zihuatanejo, Mexico. For 4 months. Hopefully we both will be accepted back to the USA. Vet check done salmonella & avian flu, FDA form. Of course riding with me in the cabin. Suggestions: he’s never had wings clipped don’t want to lose him, he is banned. Free flies all day at home, 100 yard a day… Hasn’t use a harness. NO A/C, suggestions to tolerate heat, travel cage. Cover at night a sheet?