Amos, be careful with the foam, and make sure it's covered with some kind of cloth. I did this years ago with an old Martin D-28, without covering the foam with material, and apparently there's a chemical process called 'plasticizer migration" in which the chemicals in the foam can react with the chemicals in the finish of the guitar and cause blistering. Folks, the Calton cases are superb, but they only have 2 D-rings for one shoulder strap.Here's a little trick that I did to make it back-portable. I got an extra pair of D-rings from the company, and added them to my case on the other side from the existing pair. I can now attach 2 padded straps to carry it on my back.

All the best.

Seamus