UPDATE:
The 3D printed parts are being delivered to my house TODAY. This weekend I will assemble the pack, add the hosing, and tryout the connection to the backplate. If all goes well, I will be ready to sell the first version next week.
We are creating a higher level version that will have some removable parts.
I will post pictures of the build process, but most likely I will post the picture of the finished product, first since I am impatient.