Scroll Case Long

This is just a longer version of jjansen's Scroll Case. I just wanted to make it longer so that I can fit my D&D game mat in it. I am still working on trying to figure out how to joint it so I can print it in smaller parts then glue it together. As soon as I figure it out Ill upload those parts. If anyone knows how to go about that I would like some assistance.
The game mat I am using is: https://smile.amazon.com/gp/product/B00OCYO8XK/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1