Rinse and wipe the quince with a cloth. Remove the stems and cut into wedges. Place the quince and the candy into 3-4 500 ml (approximately 17 ounce) sterilized jars. Bring the sugar, lemon juice, and 250 ml (approximately 8 ounces) of water to a boil. Once the sugar has dissolved, pour over the quince in the jars. Fill with the alcohol, until everything is completely covered. Seal tightly, and infuse for 4-5 weeks in a dark, warm place. Shake occasionally during this time.
Strain the mixture through a strainer lined with cheesecloth into clean, prepared bottles.