Marinate the pork with the lemon,garlic, oregano, salt and pepper and olive oil for as little as half hour or up to a few hours.
Prepare the grill. Thread the meat onto skewers- if you are using wooden skewers soak them in cold water for at least an hour to avoid burning. When the grill is hot, grill over direct heat turning every couple minutes until all 4 sides have a nice char. Don’t crowd them on the grill. Total cooking time depends on how hot the coals are- usually about 8-10 minutes.
To serve- place 5 or 6 pieces of meat in the middle of a warm pita- top with onions tomatoes, and lots of tzatziki.. Serve with plenty of napkins!