Hope you managed to find a Tube ... or three!
You will need them ... and finding quality ones in Mexico is not that easy.
Would love to hear about your Prep on your DR650 ... but I can't deal with Blogs.
How long to you plan to be on the road?
Good idea to have at least two ATM cards with No int. exchange fees.
Love to see some pics. Much easier than a reverse Blog with adds and other non essentials. ADV is best for all of it, IMO.
Good luck - ride safe!