Whisk 4 eggs, both cheeses, garlic, and 1/2 teaspoon pepper in medium bowl; set aside. Cook pancetta in large nonstick skillet over medium heat until crisp, about 7 minutes. Using slotted spoon, transfer to small bowl. Reserve skillet with drippings.
Cook pasta in large pot of boiling salted water until almost tender (about 3 minutes less than package directions); add broccoli rabe. Cook just until broccoli rabe is crisp-tender and pasta is tender, about 3 minutes longer. Drain pasta-broccoli rabe mixture, reserving 1/2 cup cooking liquid. Return hot pasta-broccoli rabe mixture to pot (off heat). Immediately add egg-cheese mixture, pancetta, and 1/4 cup hot cooking liquid; toss to combine, adding more cooking liquid by tablespoonfuls to moisten as needed. Season to taste with salt and more pepper, if desired. Cover to keep warm.
Heat skillet with drippings over medium heat. Crack remaining 4 eggs into skillet; sprinkle with salt and pepper and cook until whites are opaque, about 2 minutes. Carefully turn eggs over; cook just until whites are set but yolks are still soft, about 1 minute longer. Remove from heat. Top pasta with eggs and serve.