Hm, that is a bit surprising. Is there no simple way to enforce a perfectly filled buffer/requestor chest with 48 distinct item types then?

Goal : I was trying to make a buffer/requestor chest filled with 48 requests of full stacks of distinct items. I enabled 'Trash unrequested' on the chest, as I need each slot to be a different item, and not overfilled contents of other items. E.g. 100 yellow belts, 100 red belts, 100 blue belts, .....