Now I have just burned about 30 hours of my life to design a battery containment system for the 24 LiFePO4 cells that will power it. Here is the 3D model:
It will bolt in on the same mounts that used to attach the engine. This will be laser cut and tab together with a little bit of TIG welding. The transparent end caps are polycarbonate. The rest of the structure will be aluminum. I should have the parts back in hand in about 2 weeks to TIG together.