Have on hand 9 half-pint jars and sealing lids- sterilized according to the manufacturers instructions.
Cut the fruits in half and squeeze the juice out of them (save the orange and the lemon juices separately).
Chop the remaining citrus sections (yes- peel and all) in a food processor in small batches as you want the pieces to be fairly small (ideally about 1/4 inch but the sizes will vary, that is great).
Place the chopped citrus into a large pot and cover with cold water. Bring to a boil and cook, stirring occasionally, until the citrus mix is tender to the bite, about 10 minutes. Drain and rinse the fruit, clean out the pot as well.
Put the citrus mixture back into the pot with 1 1/2 cups water and bring to the mix to a boil.
Stir in the 3 1/2 cups sugar. Adjust the heat to maintain a slow simmer. Cook, stirring occasionally, until mixture is thick and creamy and the fruit is tender to the bite. This will take about 1 hour.
Taste and add up to 1 1/2 cups additional sugar to taste, add the 1/2 cup of orange juice and stir until well mixed.
Pack into the jars and process according to the jar manufacturers instructions- mine takes about 10 minutes once the water bath has returned to a boil.