Add peaches and cherries to a large mixing bowl Crush peaches and cherries using a potato masher Add lemon/lime juice and sugar and mix well Let fruit sit for 10 minutes, stirring occasionally Add water and box of pectin to a medium saucepan Heat to boiling, stirring constantly Boil for 1 minute, stirring constantly Remove from heat and add hot pectin water to fruit Stir for 3-4 minutes until mixture is no longer grainy Decant into clean jars and let sit and room temperature for 24 hours Refrigerate for up to 3 weeks or freeze for 6 months