Compute Cube w/Stack Factor

[Guest]

So I've got a bit of a problem, and I honestly can't figure out how to express this as an equation that makes any sense to anyone other than me.

I need to be able to calculate volume in cubic inches for a cargo trailer.

The available inside length of the trailer is 636 inches. Width is 102 inches and height is 102 inches. This, however, isn't my problem.

Within that trailer, are bundles of cargo (pallets typically). Sometimes they are stackable, and sometimes they are not.

Let's say I have 48 bundles that are 41 inches long, 48 inches wide and 40 inches tall. They have a stack factor of 3.

Three bundles stacked, however, exceed the maximum available height of the trailer.

How would I compute volume, when I'm confined by these specific limitations?