Need to create a function to choose and display optimal configuration of 5 box CBM's

[BlahBlahManshoes]

I am creating a box CBM optimizing tool at work for shipping our products internationally so that the sales department and logistics can estimate shipping costs and weights with out needing me to physically pack everything in advance. I have broken every product we sell into individual CBM's as well as the boxes that we use to ship. I have also set it up to give a break down of "boxes needed" to accommodate the approximated CBM by box size. What I can't figure out is how to create a function that will take that info and calculate which combination of boxes will utilize the available space... In other words, how do i take my break down of the 6 box sizes available, with the "# of boxes needed" data i already have, and have it tell me which combination of boxes will utilize the maximum percentage of space, or leave the least amount of unused space based off of the cumulative CBM being shipped. if you look at the snippet attached you can see that it would be simple enough to figure it out by using a calculator and some common sense but i cant rely on others using common sense... I need to make it idiot proof! Help?!

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[BlahBlahManshoes]

I have been playing around with conditional formatting and have only managed to highlight the closest box that doesn't go over the available CBM space... Could a Look up table be set up to perform the effect i'm after?