Grilled Shrimp without panko guacamole

1 1/2 lbs large shrimp , shelled 9 tablespoons olive oil 1/2 teaspoon dried oregano 1 teaspoon salt 1/4 teaspoon fresh ground black pepper 2 garlic cloves ,[...]

1 1/2 lbs medium shrimp , peeled and deveined (21 to 25 per pound) 1/3 cup olive oil , plus 2 tablespoons olive oil kosher salt , to taste fresh ground pepper[...]