In the bin, my boy, in the bin!!!! Render it down in a moderate oven and, if you like, render it further and you will have the loveliest lard for frying, pastry making etc. and the dogs will love the "scritchins)
do you not have dogs? try making some soap, or feed it to the wildbirds.
in my opinion the best way to finish your pigs is to feed by eye and feel their bodies. feeding by weight only will give variable results as pigs, individuals, weather, environments are all so different.
you should be able to feel their ribs and spines to a certain degree and its then not difficult to judge how much fat is covering them. if you cant feel them at all then you've fed far too much.
with a mixed bunch of 7, you will need to feed different amounts but this can be done if you can feed them all the basic ration, then bring those needing extra individually through a gateway/into a trailer for more feed. we spread the feed widely over the ground and trained them to come to call/bucket so we could manipulate the ones we needed into position. it takes time but its worth it. handling is easier if they are used to it from a young age.
have you thought about butchering your own pig occasionally, just ask for the carcuss to be split and collect it yourself from abattoir. you learn so much about fat dispersal this way.