A bit off topic, but...
I have seen the 5-S stuff in action. Properly done, it does actually work. Works well enough that in the industry I work in (window and door manufacturing), my employer is still going steady and is busy all year, while some other local companies barely work 24 hrs per week.
IMO, however, a better option than using all that foam would be to just work on a better layout for all the stuff you have. I've "preached" this before. I have seen some people who have the huge boxes, and have over half of it filled with needless items. Old carb parts, pinion seals for a '49 Olds, you name it. Some others have a single older "mini" roll-away cabinet and they have only the stuff they need in it.
In a while, Chet.