This video was such a HUGE help in building my own pack. Thank you so much for detailing your process. I probably watched this video 50 times while building mine.
If anyone's wondering how thick the EVA foam mats are, I eyeballed it and they look like they are 1/2 an inch thick. (EDIT: I reached out to him and it turns out that they were actually 1/4 inch thick. I personally used 1/2 inch thick foam and it worked out okay, albeit a little tough to cut and bend into shape. )