Don’t rely on anything with adhesive. The heat and humidity is a bitch and will kill all adhesives. The frame for my Zacuto Z-finder came off after a few days of shooting, so find another solution if any part of your kit relies on adhesive.
Bring rechargeable batteries for every part of your kit, batteries will die fast in this heat and you’ll want to keep them at a full charge.
Get a nice, lightweight tripod. The Benro Aero 4 has been excellent for me, nice balance of lightness and durability.
Download all updates, fonts, music, and other assets before and store them locally. You will not want to have to use the Internet here to download anything but a small PDF.
Bring a lens cloth and lens cleaner. Watch out for lenses fogging up in the humidity, I was out in the fields here shooting in the morning and I lost a few shots due to fog.
Bring a backup battery charger for your camera’s batteries. I was an idiot and somehow forgot my LC-E6 for my Mark III before I got here and it took me a week to find a place in San Jose with one. There are relatively frequent power surges and low flows here than can kill electronics, and if you find yourself down here without a charger you will be SOL.
Get a nice lav mic if you don’t have one, like the Sennheiser G3 kit. They are pricey but so worth it and so durable (it’s been dropped tons of times and is still in great shape). The cicadas here are really, really loud and even a well-placed shotgun mic doesn’t do a great job of knocking them out. Bad video footage can be overcome but bad sound makes stuff unwatchable. Spend the money and get the quality.