Iberian Union Holds Up
A first world Latin America would require a concentrated immigration and capital infusion along the lines of the British colonization of the 13 colonies.
My favorite POD would be Philip the IV of Spain working to strengthen the ties between Portugal and Spain, preventing the revolt of Portugal in 1640 and the breakup of the Iberian Union. By 1700, the two nations had effectively merged as one, united under conflict with the Dutch for various colonial possesions in Brazil, India, and Africa.
Instead of the eventual decline of the two seperate Spainish and Portuguese Empires, combined they held their major colonies in South America, and continued to trade at a level equal to the British Empire. When Napoleon came to power, the Iberian Empire started to invest in development of Brazil, and used it's naval power to tighten control of world trade while England fights France.
By 1900 Brazil has developed to the point of Pre-ACW United States, and gradually gains independance from the Iberian Union.
<WHOOPS POST 1900 POD, MY BAD>