Dice the pork into manageable pieces; combine in a large pot with orange juice, fresh lime, canola oil, onion, cloves and chicken stock. Let mixture sit for 1 hour. Next bring to a gentle simmer, simmer uncovered for 3hrs. until the pork is fork tender.
In a large pot add the onion, tomatillos, garlic and guajillos. Lightly char until tomatillos are blistered and aromatic. Remove the mixture and add to a blender along with the salt.
Pour a generous amount of the salsa on to the plate and add the pork carnitas, pour more salsa on top if desired.