few hundred lb of oranges/apples/tangelos

[Switcher]

Where i work we had a fruit sale of oranges/apples/tranergines/tangelos and they ordered a few too many boxes. Like 15 40lb boxes, i was told to get rid of them so i thought about making a mash from them. Some of them are getting soft/are soft/rotten/almost moldy. Just wondering what a guideline for how many pounds of fruit(peeled/seeded?), and how much more surgar i would need to add depending on what fruit i would use. Most likely be the oranges and apples unless someone recommends against it. Usually 5gallon batches, quick reply would save a few oranges lol, thanks.