Exporting commercial trucks to latin america?

Hello fellas, I bought two 2001 freightliner century with flatbeds that i need to bring down to central america for personal use. Now, I dont belong to any trucking company. I have heard all kinds of comments, but mostly from inexperienced guys I need somebody who can explain me clearly what legal stuff do I need to cross this trucks legally from Fontana, CA - all the way to central america. first of all which US borders allow me to drive this trucks across..? also Is it true I need to get a so famous USDOT number... and if so, how do i get it? and how much is it,.. I really need a detailed explanation about this whole process. like i said before i have no experience whatsoever about this, I do have my drivers ready and the trucks with title in hands. I've done some research online but i'm still in the clouds, if you can also provide me links and phone numbers that would be awesome. Thanks a lot guys!