Irritatingly, my original idea of mounting the battery inside the old fuel tank hasn't worked.
The size of these pouch cells also means they don't fit if they are all connected together in one brick.
Instead, I will split the pack into two: the "main" of 11 cells and then the "side" of 3 cells. These can be connected with high voltage wires and will function as one pack.
While this is a shame, I've managed to mount the charger plug within the original fuel cap. This is great and really helps with it hiding it's new electric heart!
