After a generous offer of free fruit, I decided to forget about classic recipes and combine ingredients in my own way, based on the fruit at hand. As a rough guide I looked at proportions of sugar to fruit in classic recipes. Not a bad result, although I may use less sugar next time, and grate in the lemon peel.
4C Mariposa (red) plums
3C orange rind and pulp
1 large lemon for juice
1 pkg Certo liquid pectin
Peel and pit the plums, then toss in a food processer and pulse to rough chop, then set aside. Boil the orange peels from 3 large oranges for 30 minutes until softened, set aside to cool, then slice very thin and place in a measuring cup, fill to the 3C mark with chopped orange sections that have been peeled and trimmed. Now finely chop fresh pineapple to fill to the 4C mark. Mix all ingredients in a non reactive 4 quart sauce pan, then add the sugar and mix well. Use medium heat to boil the mixture until it reduces by about 1/4th, then add pectin, stir, bring back to a boil for one minute, then place in sterilized jars, seal and place in a water bath for 10 minutes.