Racial politics in Colonial Spanish America were an intricate set social tiers that recognized European-born whites, American-born whites, Africans, and Native Americans and mixtures between those people as members of different racial groups. How could a similar system be adopted in the British colonies?
Firstly, at risk of stating the obvius, white people are originally from Europe. So, Peninsular wasn't a new group, criollo was. Concerning British America, we can trace an American identity back to the ARW, maybe earlier during colonial times, but it wasn't as strong as the criollo/peninsular identity.
The rivalry was clearly about official positions. In Spanish America we had i) a big bureaucratic corpse and ii) a huge (and locally educated) aristocracy. In Brazil, for instance, there wasn't a clear divide between Portuguese and Brazilian whites. There was, indeed, an important bureaucratic machine, but Brazilian-born elite was uneducated and needed to study in Portugal to aspire to a colonial position.
In British America, the colonies were small and administrated separately (and much more autonomous than Iberian America), limiting the size of the bureaucracy.
NOW - the hardest part -, to create a different mixed-race castas, well, risking stating the obvious again, you will need mixed-raced people. And, for that, you pretty much need to change the entire colonial history of the US.