With a sharp knife, slit the sausage skins lengthwise and pop all the meat out. Using wet hands, roll little balls of sausage meat about the size of large marbles and place them on one side.
Heat a large frying pan and add a good splash of olive oil. Gently fry the sausage meatballs until golden brown all over, then add the pancetta and continue cooking for a couple of minutes, until it's golden. While this is cooking, bring a pot of salted water to a boil, add the linguine, and cook according to the package instructions.
In a large bowl, whip up the egg yolks, cream, half the Parmesan, the lemon zest, and the parsley. When the pasta is cooked, drain it in a colander, reserving a little of the cooking water, and immediately toss it quickly with the egg mixture back in the pasta pot. Add the hot sausage meatballs and toss everything together. The egg will cook delicately from the heat of the linguine, just enough for it to thicken and not scramble. The sauce should be smooth and silky. If the pasta becomes a little sticky add a few spoonfuls of the reserved cooking water to loosen it slightly. Sprinkle over the rest of the Parmesan, season if necessary, drizzle with extra virgin olive oil, and serve. Eat immediately.