Place pork in large self-sealing bag. Add olive oil, lemon juice, oregano, salt, pepper and 6 garlic cloves to bag; seal bag and toss gently to combine thoroughly. Refrigerate 8-24 hours. Remove pork from marinade; discarding marinade.

Prepare medium-hot banked fire in covered kettle-style grill. Grill pork over indirect heat, away from fire, for 45 minutes-1 hour, until internal temperature reads 150-155 degrees F. Let rest 10 minutes before slicing to serve with Yogurt Sauce.

For Yogurt Sauce, stir together yogurt, cucumber, onion, 1 garlic clove, coriander, salt and red pepper flakes. Cover and refrigerate until ready to serve.