Preheat your oven to 350˚ F. Slice pre-baked in half length-wise. Carve out the insides of the potato halves with a sharp knife, and scoop out the potato with a spoon. Be sure to leave enough potato to support the shell of the potato skin. Reserve for another use.
Rub olive oil over the inside and top edges of the hollowed potato. Sprinkle a pinch of salt and pepper on the potato. Spread 1 teaspoon Parmesan cheese on the inside of each potato half. Divide the shredded cheese (Manchego) between the two halves, and sprinkle on top of the Parmesan. Divide the green onion between the potato halves, and add to the top of the cheeses.
Slide into the oven to warm the potato and melt the cheeses, about 10 minutes.
Melt the butter in a medium-size skillet over medium heat. I recommend a skillet with a protective coating to prevent sticking. Gently crack the eggs into the skillet, and cover. Cook for 3 - 4 minutes, or until the tops of the eggs are cooked, but the yolks are still runny.
Remove the potato halves from the oven, and arrange the guacamole slices in them. Top with the fried eggs, a flurry of the remaining Parmesan cheese, salt, pepper, and oregano.