Marinade:
Make the marinade by combining all the ingredients together. Arrange the partridges in it and cover it, letting them marinade at least over night.

Stuffing:
Heat the olive oil in a skillet and sauté the onions and garlic. Mix in the livers and cook them until the red color disappears then toss in the mushrooms and celery. Add the wheat, chicken stock and the tomato paste. Stir it well until the paste dilutes. Add the seasonings and simmer for about 25 minutes or until the stuffing is thick. Remove from the heat and let the stuffing cool.

The Birds:
Preheat the oven to 400F. Stuff the partridges and sew the openings closed or use skewers to secure them. Turn the wings under the birds and tie the legs together. Arrange them in an oiled roasting pan, side by side with the breasts up. Pour olive oil generously over the birds. Roast them for about 10 minutes uncovered. Turn them to one side and baste with the oil, then return the pan to the oven for about 15 minutes. Take them out again and turn them on the other side and baste before you return them to roast for another 15 minutes. Ending with the breasts up, baste them often as they finish cooking. The skins should be golden brown and the legs should pull away easily. Carefully remove the strings or skewers and move them to a warm platter and serve.